0 Administrative Information about the Statistical Product


0.1 Name
Harvest of cereals etc.

0.2 Subject Area
Agriculture

0.3 Responsible Authority, Office, Person, etc.
Food Industries
Merete Iisager, phone + 45 39 17 33 87, e-mail: mpr@dst.dk
Ina Nylander, phone + 45 39 17 33 88, e-mail iny@dst.dk
Torben Pedersen, phone +4539173382, e-mail: tpe@dst.dk (coarse fodder)

0.4 Purpose and History
Statistics Denmark compiles statistics on the Danish harvest of cereals on the basis of data reported by farmers. The purpose is to estimate the harvest of cereals, rape and pulses for maturity as well as coarse fodder. Harvests of cereals for silage or green fodder are included in the survey of the harvest of coarse fodder.

Final statistics of crop yields are available as far back as 1875.
As part of the cereal harvest surveys, the production and use of straw are compiled. Annual surveys of production have been conducted since 1970 and use of straw since 1972. Furthermore, separate surveys of straw for fuelling have been
conducted for the years 1992/93, 1994/95 and 1996/97 at the request of the Danish Energy Agency.

Finally, the statistics on cereals production includes a forecast for sowed areas with winter rape for harvesting in the subsequent year. Since 2002, these estimates have been based on the amounts of certified seed grains. The results are of importance to forecasts of the forthcoming harvest. Forecasts have been conducted since 1967.

As part of the crop yields, statistics on the production of seeds for sowing are also compiled.

Statistics on coarse fodder are available as far back as 1900. Since 1964 questionnaires covering questions about the yield per hectare of grass have been sent to plant breeder consultants. In 1980 the questionnaires were extended to include grass and green fodder products: In 1982 questions about beet roots and potatoes were added to the questionnaires. From 2002 there are separate questions on organic and conventional production.

0.5 Users and Application
The most important users are the EU and agricultural organisations. The data on production are also used in compiling the Economic Accounts for Agriculture (EAA). The use of straw for fuel is used by, e.g. the Danish Energy Agency.

0.6 Sources
The results from separate questionnaires and information on land use from the Agricultural and Horticultural Survey conducted by Statistics Denmark are used in compiling the statistics.

The data from the Plant Directorate on certified seeds and previous harvest surveys are used when forecasts for areas with winter cereals are conducted.

The results with regard to seeds for sowing are based on data from the Plant Directorate.

For the compilation of statistics on coarse fodder, area data are supplied by the Danish Food Industry Agency and data collected via questionnaires are provided by plant breeder consultants.

0.7 Legal Authority to Collect Data
The Act on Statistics Denmark, as the respondents (consultants) are not legally liable to report data.

0.8 Response burden
1.1 man-years, app. 347.000 DKK

0.9 EU Regulation
Council Regulation 543/2009 relating to crop statistics and forecasts.
Directive 1989/130 relating to production of straw incorporated in the Economic Accounts for Agriculture.


1 Contents


1.1 Description of Contents
The statistics on harvest of cereals, rape seeds, pulses and straw are, first and foremost, part of the agricultural production statistics.

The part covering cereals, rape and pulses provides data on crops (winter wheat, -barley, -rape; spring wheat, -barley, -rape, rye, oats, triticale, mixed cereals and field peas). For each type of crop, questions are asked about arable land, total yield (hkg), average yield (hkg/hec) and moisture percentage. The latter information is used in calculating production to standard moisture content (15 pct. for cereals and pulses, and 9 pct. for rape seeds).

The statistics on straw show the production and use of straw for the above-mentioned crops. The production is estimated on the basis of a ratio between yield of cereals, rape, pulses and straw yield for the different crops, while the use of straw for, respectively, fuel, feeding stuffs for animals, other uses or for ploughing-in, is based on data from the questionnaires filled out by the farmers.

Furthermore, information on grass as aftermath in fields with cereals for maturity is collected, and the results are included in the statistics on coarse fodder.

For the survey of coarse fodder, information is collected from about 50 plant breeder consultants concerning yield per hectare for grass (grass in rotation and permanent grassland), greenfodder (maize and whole crops), beet roots (commercial beets and fodder beets) and potatoes (for human consumption, industrial use and seed potatoes). Since 2002 separate data have been collected with regard to the yields derived from organic production of grass, whole crop and potatoes for human consumption. From 2005 the collection of information on beet tops was discontinued due to the minor importance of the product. Central yield estimates for crops as aftermath and conversion factors between volumes and feed units are collected from the Danish agency for cultivation of plants. Information on yields is combined with information on land use from the Danish Food Industry Agency (since 2005) and the Agricultural and Horticultural Survey conducted by Statistics Denmark and thereby it is possible to calculate the total yield of coarse fodder.

As from 2006 the results are calculated on the basis of the new administrative structure in Demark, i.e. for regions. The regions are divided by special agricultural provinces (sub-divisions of regions). It has been decided to merge the results for the provinces Copenhagen Town, Copenhagen suburbs and North Zealand into one group called "Copenhagen and North Zealand" and also for the provinces East Zealand and West Zealand., which coincides with Region Zealand. Region placeNorth Jutland has not been divided into provinces. The division is as follows:

All placecountry-regionDenmark

Region the Capital of placecountry-regionDenmark

placePlaceTypeProvince PlaceNameCopenhagen PlaceTypeTown, Province Copenhagen suburbs and Province North Zealand

Province placeBornholm

Region placeZealand

Region placeSouth Denmark
Region Funen, including the islands
Region placeSouth Jutland

Region placeCentral Jutland
Province placeEast Jutland
Province placeWest Jutland

Region placeNorth Jutland

With respect to the statistics on areas sown during autumn for the next years harvest, areas for winter-wheat, winter-barley, rye, triticale and winter-rape are estimated. The estimate only covers the total area of placecountry-regionDenmark.

The survey of the use of straw for fuel is based on a sample of farms selected from farms having stated via the Agricultural and Horticultural Survey that they have a fuelling system using straw. The farms selected for the sample are questioned about the quantity of straw used within their own farms, broken do own by use for farming and dwelling, and the quantity of straw (or energy) provided to others.

The results with regard to seeds for sowing (areas, yield per hectare and total production) are compiled for about 20 types of grass seeds.

1.2 Statistical Concepts
The harvest survey of cereals, rape seeds and pulses, including the production and use of straw, is based on a sample, and the results are calculated using the population of farmers as described below.

Population: All agricultural and horticultural farms, which had a total arable land of at least 5 hectares or agricultural production corresponding to this, are included in the population. In 2006 the population comprised almost 40,000 farms.

Sample size: 3,000 farms are selected from the sample used for last years agricultural and horticultural survey, which comprises 20,000-25,000 farms. The reason for the selection method is to ensure that only newly updated farms are drawn in order to minimize the risk of sending questionnaires to farmers, who are not engaged in the production of cereals.

Stratification: The sample selection is conducted by stratified random sampling. From 2007 the process of stratification is undertaken according to the location of the farm in 10 areas based on the 11 provinces (previously counties), size of the farm in terms of arable land with cereals, pulses and rape seeds and a sub-division according to Standard Gross Margin (economic size indicator for farming). From 2007 the farms are divided into 80 strata. The total sample number is allocated to the strata to ensure national results with the lowest possible number of statistical errors.

Sample selection: The sample is selected by undertaking stratification, random sampling from the sample used for the Agricultural and Horticultural Survey. However, at least 80 farms are drawn from each province. A new sample is selected each year.

Raising method: The crop yield is only calculated for the production of cereals, pulses and rape seeds. The average crop yields measured in terms of hkg per hectare in each stratum in the sample survey are first calculated on the basis of data on yield and on area of each farm. Subsequently, the average crop yields in each stratum are multiplied by the areas in each stratum in order to arrive at total figures for the crop yields. For the crop yield, results are calculated for aftermath in fields with cereals and for straw as well as the areas from each stratum of the Agricultural and Horticultural Survey of the same year. The areas have been adjusted for areas of farms under 5 hectares, which are outside the scope of the Agricultural and Horticultural Survey. From 2005, the calculation of the areas from the Agricultural and Horticultural Survey is verified with the totals from the farmers applications for EU subsidies.

In relation to area data from the Agricultural and Horticultural Survey, there are instances where data for areas reported in the spring as cereals for maturity might, instead, have been harvested as cereals for whole crop and reversely. This implies that the figures are not completely reliable. In order to examine the need for area changes, the areas of the farms, which are included in the Agricultural and Horticultural Survey as well as the survey of crop yields in the year in question, are compared, but only for farms with livestock, where there might normally be changes. If any systematic changes are found, the areas are subject to corrections.

Before 2001 the data reported on crop areas for cattle were directly used in the calculation of areas, but due to a non-randomly selected sample, this did not result in a fully representative correction.

It should be noted that in cases where there are only 2 farms or fewer in a single stratum, the average crop yield in the stratum in question is equal to the average of the province. Similarly, there are no more than 2 observations at province level; the crop yield is equal to the national average of the crop in question.

Finally, it applies that data from the sample on the moisture percentage of cereals harvested are used in order to convert yields of cereals into a moisture percentage of 15 cereals (applying from the 2001 harvest). Up to and including 1988, the standard moisture on cereals was 16 per cent.

Calculations in connection to harvest results
The harvest volumes of cereals are also shown in Feed Units. The conversion factors used are 1 FU = 0.97 kg wheat, = 0.00 kg rye, = 0.98 kg triticale, = 1.05 kg barley, = 1.26 kg of oats. For peas and other pulses 1 FU = 0.92 kg and for rape seed 0.59 kg. The factors were revised in 2002 and have formed the basis for the calculation since the 2001 data and onwards. The conversion factor from 1996-2000 appears from an article in the series Statistical News 2002:7.

The calculation of straw produced is based on an estimated relationship between volume of grain and volume of straw. For winter wheat, winter barley and spring barley 55 kg straw per 100 kg grain are expected from 2003. The factors for rye and triticale are 80, for oats 60, for spring wheat and peas 50, while 90 kg are expected for 100 kg of rape seeds. The conversion factors are expected to provide a representative calculation for years in which weather conditions are considered to be normal. In other years, there might be great fluctuations in relation to the above-mentioned factors.

For the calculation of straw into feed units the following conversion factors are used from 2001. 1 FU = 5.5 kg straw from wheat, 7.5 kg straw from rye, 5.0
kg straw from barley, 5.5 kg for straw from oats, triticale and mixed cereals, 4.0 kg straw from rape seeds and 3.5 kg of straw from pulses.

Calculation of forecasts for winter cereals
The forecast for sowing of winter cereals and winter rape is based on the actual certification of seeds combined by the relationship between the quantity of certified seeds and harvested areas three years prior to the year of forecast.

However, figures for winter rape provided by The Farmers Advisory Service are used. The figures are based on quantities of seeds sold for sowing of various kinds of winter rape.

Coarse fodder
Population: About 50 plant breeder consultants in placecountry-regionDenmark.
Variables: Average yields for the relevant crops, production measured in terms of kg and/or fodder units. Areas of grass, green fodder, beet roots and potatoes are based on the Agricultural and Horticultural Survey. However, from 2005 the figures are verified with the totals from the farmers applications for subsidies.

Calculations related to the harvest
Similar to the harvest of cereals, the harvests of potatoes, beet roots, grass and green fodder are measured in terms of volumes as well as feed units. This implies that the harvest of potatoes and beet roots is converted into feed units, whereas the harvest of grass and green fodder is converted into feed units to volumes.


The following conversion factors are used for the most important crops. 1 FU = 5.25 kg of seed potatoes, = 3.66 kg of starch potatoes, = 5.09 kg of potatoes for human consumption, = 4.62 kg of beets for sugar production, = 3.77 kg of silage maize, = 3.59 kg of silage cereals; 5.89 kg of grass in rotation and = 6.28 kg of grass from permanent grassland. The conversion factors represent years in which weather conditions are normal and may thus differ somewhat in other years.


2 Time


2.1 Reference Period
With respect to the harvest of cereals, rape seeds and pulses, the reference period is at the end of the harvest of each year, typically at the beginning of September.

With respect to forecasts, the data as of October 15 are used, as this date is usually considered to be the latest possible time for sowing in the autumn.

Data on seeds for sowing only appear in Statistics Denmarks annual agricultural publication.

Data on the harvest of coarse fodder are published annually at the end of the year, usually in November.

2.2 Date of Publication
The statistics are published annually.

Provisional figures for the harvest of cereals, rape and pulses are published at the beginning of November and final figures are available in April of the following year, when the statistics on the harvest of coarse fodder are also published.

The forecast for areas with winter seeds of the following year appear at the beginning of November.

Data on seeds for sowing appear in Statistics Denmarks annual agricultural publication.

2.3 Punctuality
The statistics are published as scheduled.

2.4 Frequency
The statistics are published annually.


3 Accuracy


3.1 Overall accuracy
The overall accuracy of the statistics on the harvest of cereals is considered to be good. However, there is some uncertainty with respect to crops grown in small areas at national level, particularly with regard to spring rape.

The accuracy of the forecast for areas with winter seeds is generally considered not to be quite satisfactory, compared to the harvest.

The accuracy of coarse fodder is considered to be reasonably with regard to the average yields, while it is considered to be very high for the area data.

3.2 Sources of inaccuracy
With respect to the harvest, where the sample survey comprises about 3,000 farms, corresponding to approximately 8 pct. of all farms, some margins of statistical errors must be expected, which have not been calculated for the years before 2004. For a description of the estimation procedure of the harvest results, etc. see item 1.2.

Concerning the questionnaire-based data, the greatest margins of statistical errors are related to the data on the use of straw, particularly because straw is frequently gathered-in and used by neighbouring farms or agricultural machine pools, where the person in charge at the selected farm does not always have full knowledge of the use of straw.

The calculation of the production of straw is subject to some uncertainty with regard to some single years, as the relationship between crop yield and straw yield fluctuates in accordance with weather conditions, etc. The relationship is updated at intervals of 5-6 years.

The response rate of the questionnaire-based survey is generally over 90 per cent and consequently does not cause any uncertainty as such.

Concerning the forecast, it is based on the assumption that certified seeds are used in the same year in which they were certified. However, changing weather conditions may imply that this assumption is not fully correct, and consequently the stocks of seeds will have an impact on the forecast. Furthermore, sown areas may be damaged by severe weather during winter.

Finally, the use of seeds for sowing from own produced cereals (not certified) may fluctuate from one year to another.

With regard to coarse fodder, the information about yields is based on estimates made by the plant breeder consultants, and is consequently subject to margins of errors, because it is, of course, difficult to estimate the production of green fodder. The information about agricultural areas is submitted by the Directorate for Food, Fisheries and Agro Business and is considered to be highly reliable, as the information is thoroughly checked by the Directorate. The response rate of the survey is somewhat lower than 100 per cent, which may cause uncertainty.

3.3 Measures on accuracy
Sampling errors have been calculated annually as from 2004. The standard deviation of errors with respect to the total harvest of cereals, rape and pulses is in the region of about 0.3 per cent, corresponding to about 30.000 tonnes of cereals.

Concerning crops with a small total area, the standard deviation of errors may reach up to 5 per cent. The errors are within the accepted limits in the EU Regulation on crop yield statistics.

Due to the greater spread of the use of straw than is the case with respect to crop yields, the margins of statistical uncertainty concerning the use of straw for different purposes will be relatively greater than the statistical uncertainty concerning the harvest of cereals, rape and pulses.

The relationship between the areas in the forecast and the later established areas indicates that there is a statistical uncertainty in the region of 5 per cent for the total areas with winter seeds.


4 Comparability


4.1 Comparability over Time
The final figures on crop yields are, in principle, comparable as far back as 1900. However, changes in methodology must be taken into account, but the present compilation method has been used since 1971. The results on crop yields at regional level are only comparable as from 2006 due to a new administrative structure of placecountry-regionDenmark. For this year, results are compiled on the basis of the former counties as well as the present regions.

Figures on coarse fodder are fully comparable as from 1982 and onwards. The change in methodology, which applied for the 2001 survey to the 2002 survey (taking specific account of organic production) as well as the change in the basis of areas (from 2005) may, to a minor extent, have an impact on the data comparability.

4.2 Comparability with other Statistics
The forecasts for areas with winter seeds can be compared with the later results on areas according to the Agricultural and Horticultural Survey.

4.3 Coherence between provisional and final statistics
Prepared only once every year, and consequently provisional and final figures cannot be distinguished.


5 Accessibility


5.1 Forms of dissemination
The provisional statistics on crop yields appear in Nyt fra Danmarks Statistik (News from Statistics Denmark). The final statistics on crop yields are published in Landbrug (Agriculture) appearing in the series Statistiske Efterretninger (Statistical
News).

Annual publications: Statistisk Årbog (Statistical Yearbook), Statistisk Tiårsoversigt (Statistical Ten-Year Review) and Landbrugsstatistik (Agricultural Statistics).

Figures are also available from www.statbank.dk/hst6, /hst7 and /hst5 and/ (forecast)

5.2 Basic material: Storage and usability
The survey data are electronically maintained for a number of years and may be used for conducting further analyses. For further information, please contact the responsible person, see item 0.3.

Questionnaire-based data on coarse fodder were registered in Blaise in the period 1993-2003. From 2004 data on coarse fodder are registered in Excel spreadsheets.

5.3 Documentation
Methodological descriptions are published in Landbrug (Agriculture) appearing in the series Statistiske Efterretninger and in the annual publication Landbrugsstatistik (Agricultural Statistics).

However, the present declaration of content provides a more detailed description.

5.4 Other Information
No other documentation is available.


Supplementary documentation
No supplementary documentation is available