At the elevator I worked at we always took off 1/2 of 1% of the grain that we turned per month.. so with stocks at 14.26 byn bushels.. each turn would amount to..  71 myn bushels.. field to elevator..1.. turn it..2.. load it out..3.. to terminal.. 4.. etc.. probably turns an average of 4..5..6 times if 5 then the amount of grain turned to dust would be 5 x 71 = 355 myn bushels..  There's no place for shrink in the WASDE.. but we all know that it occurs.

After the WASDE report USDA updates it's yearbook which gives us usage by quarter for corn.. here it is.

 ( http://www.ers.usda.gov/data-products/feed-grains-database/feed-gra...  )

From an earlier post.. ( http://talk.newagtalk.com/forums/thread-view.asp?tid=605558&pos... )   I built this burn table..  It needs to be updated.. which I do not have time for but.. you get the idea.

 I cross referenced the WASDE above with the expected Farmer Marketing percentages by month from the MYA updates at KSU..

 ( http://www.agmanager.info/crops/insurance/risk_mgt/rm_pdf14/AB_Est-...  )

to build this burn table by quarter..

So as you can see looking at the farmer selling minus demand column the first two quarters show where farmer selling exceeds usage and commercials should be able to accumulate stocks..  However, the final quarters reverse and Hedged inventory comes out to meet demand.  

Caution.. the MYA farmer ESTIMATES are historical averages (or however KSU comes up with them from NASS..) and they can change.. this is WHAT is affecting basis from a NATIONAL perspective.. 

Obviously we know that THIS YEAR a lot of the bushels are in in the Upper Midwest.. that need to make their way to the Eastern Cornbelt and South into Broiler country (Arkansas.. etc) as well as for export to NOLA.  So if we did this by a regional basis we could add some more color to the situation. 

Storing a big crop will incur shrinkage.. as noted above.. and farmers have been holding fairly tight.. as we go into the weather markets.. commercials will still need to source bushels.

edit add: I suspect that the WASDE reconciles it's shrink over Crop size.. (2010) and feed usage and OTHER.. etc.. but it gets buried in the numbers...  ???