February 2, 2010

MEMORANDUM

TO:			Air Docket EPA-HQ-OAR-2005-0161

SUBJECT:	Details on the Adjustment of Sugarcane Data Based on Marketing
Year Data in the FAPRI-CARD Models

The FAPRI-CARD models report data in terms of marketing years for a
variety of commodities.  Marketing years for different commodities do
not necessarily equal the same timeframe of other commodities.  For
instance, the crop sugarcane marketing year for “2011/2012” (October
1, 2010 through September 30, 2011) is more closely aligned in terms of
time (months) with the “2010/2011” marketing year for corn
(September 1, 2010 through August 31, 2011), rather than the
“2011/2012” marketing year for corn.  Therefore, for the purposes of
the final rulemaking analysis, data for sugarcane that are presented in
terms of marketing years are shifted by one marketing year to more
closely align with corn and other commodities in order to capture a more
accurate representation of changes in acres and other variables in a
given year.  

It should also be noted that the FAPRI-CARD models present various data
in terms of marketing years, as well as calendar year.  Any data
presented in calendar year form (e.g., “2022”) represents data
covering January through December of that year.

Raw data provided from the FAPRI-CARD models for each of the cases do
not reflect this adjustment.

This analytical decision to adjust this data based on marketing year in
this manner was made in consultation with the staff at the Center for
Agriculture and Rural Development (CARD) at Iowa State University who
operate the FAPRI-CARD models.

