Following are a series of slides looking at the accuracy of Kansas Wheat Yield, Production and implied Harvested Acreage projections since year 2000. Also, the production history of the primary Great Plains Hard Red Winter Wheat states over the 2007-2013 period is also presented. This information is also available on the KSU Agmanager website (http://www.agmanager.info/) in a document at the following web address: http://www.agmanager.info/news/Articles/KSRN_GrainOutlook_05-02-14.pdf
A. Kansas Wheat Tour Yield
The 2014 Kansas Wheat Tour projection of 33.2 bushels per acre is the lowest tour estimate since 32.7 bushels per acre in 2001 (a year in which final Kansas wheat yields ended up being 40.0 bu/ac). Over the 2000-2013 period, Kansas Wheat Tour projections have averaged 1.5 bu/ac or 4.8% higher than final Kansas wheat yields. These results are skewed by some notable yield forecast underestimates, such as the 2003 estimate of 38.8 bu/ac which ended up being 48 bu acre, and the 2001 estimate of 32.7 bu/ac which ended up being 40 bu/ac.
Of course, there were also some notable yield forecast overestimates, such as as the 2007 estimate of 41.0 bu/ac which ended up being 33 bu acre, and the 2006 estimate of 46.2 bu/ac which ended up being 40 bu/ac. As some independent market analysts have pointed out – there seems to be an interplay between declines in early estimates of Kansas harvested acres from the Kansas Wheat Tour and the USDA with the level of final yields. If harvested acres are lowered, due to acreage abandonment, etc., then the final wheat yield on the remaining acres that actually ARE harvested will be higher than they would have been if the “zero’d out wheat yield acres” were accounted for.
B. Kansas Wheat Planted and Harvested Acres
The data aspect of the Kansas Wheat Tour that is often not focused is the implied projection of harvested acres. For 2014, the implied harvested acres for Kansas wheat would be 7,852,222 acres, based on production of 260,693,740 bushels divided by 33.2 bushels per acre. With the USDA projection of 9,300,000 wheat acres planted in Kansas in 2014 (from the USDA Prospective Plantings report on March 31, 2014), percent harvested-to-planted acreage calculates to be 84.4% (i.e., 7,852,222 acres harvested divided by 9,300,000 acres planted).
Over the 2000-2013 period, Kansas Wheat Tour projections have averaged 179,417 acres or 2.0% lower than final Kansas wheat harvested acreage. These results are skewed by some notable Kansas harvested acreage forecast underestimates, such as in 2003 (619,557 acres too low), 2005 (414,286 ac. too low), 2006 (541,823 ac. too low), 2009 (630,882 ac. too low), 2011 (1,036,364 ac. too low), 2012 (775,967 ac. too low),and 2013 (781,995 ac. too low). Of course, there were also some notable harvested acreage forecast overestimates, such as in 2004 (991,979 ac. too high), and 2007 (978,049 ac. too high). Average Kansas wheat % harvested-to-planted acreage as estimated by the USDA over the 2000-2013 period is 90.8%, compared to the Kansas Wheat Tour projections over the same period of 88.9%. So, there is on average a little bit more acreage abandonment has occurred in Kansas over the 2000-2013 period than anticipated by the Kansas Wheat Tour.
A standard deviation of 633,234 in Kansas wheat harvested acreage prediction accuracy over the 2000-2013 period indicates that the 67% forecast range for the 2014 Kansas wheat harvested acreage estimate used by the Kansas Wheat Tour is 7,852,222 acres +/- 633,234 acres, or a “relatively wide” 67% likelihood range of 7,218,988 to 8,485,456 acres. In so many words, there is still a lot of uncertainty regarding what final Kansas wheat harvested acreage will be in 2014.
C. Kansas Wheat Production
For 2014, the Kansas Wheat Tour projected Kansas wheat production to be 260,693,740 bushels – comparable to recent low production years of 276.5 million bushels in 2011 and 270.6 million bushels in 2002.
Over the 2000-2013 period, Kansas Wheat Tour projections of Kansas wheat production have averaged 5.1 million bushels or 2.8% high than final Kansas wheat production as reported by the USDA. These results are skewed by some notable Kansas wheat production forecast underestimates, such as in 2001 (50.4 million bushels too low), and especially 2003 (116.0 mln. bu. too low). There were also some notable Kansas wheat production forecast overestimates, such as in 2007 (108.9 million bushels too high).
A standard deviation of 53.4 million bushels in Kansas wheat production prediction accuracy over the 2000-2013 period indicates that the 67% forecast range for the 2014 Kansas wheat production estimate used by the Kansas Wheat Tour is 260.7 mln. bu. +/- 53.4 mln. bu., or another “relatively wide” 67% likelihood range of 207.3 to 314.1 mln bu.. Though valid statistically, the low end of this range of 207 mln bushels seems unreasonable – likely only to occur under prolonged, extreme drought and crop stress over the May-June 2014 period. Similarly, the upside of this range of 314.1 mln. bu. “could” occur, but near idea growing weather during May-June would be needed to help currently vulnerable secondary tillers to develop and produce such yields. As we say in Kansas – “time will tell!”