This page contains information about data sources and limitations for SOI's Exempt Organizations' Unrelated Business Income (UBI) Tax study.

Please visit the Exempt Organizations' Unrelated Business Income (UBI) Tax to access the annual data tables and articles from the study.


The unrelated business income statistics of nonprofit charitable and other tax-exempt organizations produced by the Statistics of Income (SOI) Division are based on a sample of Forms 990-T, Exempt Organizations Unrelated Business Income Tax, filed with the Internal Revenue Service for a specified tax year. In order to qualify for the sample, a tax exempt organization must earn the filing threshold of $1,000 or more from regularly conducted business activity that is not substantially related to its exempt purpose.

The SOI Form 990-T study incorporates a two-stage sample design consisting of a stratified random sample and a special "integrated" sample. The stratified random sample is designed to represent the entire population of Form 990-T filers reporting unrelated business income. The integrated sample is designed to gather information on "related" (tax-exempt) and "unrelated" (taxable) income and expenses for section 501(c)(3) nonprofit charitable organizations that filed both Form 990 (or Form 990-EZ) and Form 990-T. This sampling program ensures that the SOI sample of Forms 990-T includes any qualifying unrelated business income tax returns filed by organizations whose Form 990 or Form 990-EZ information returns were selected for the separate SOI sample of section 501(c)(3) nonprofit charitable organizations. Organizations exempt under other Code sections were not subjected to the integrated sampling program. The designed sampling rates ranged from a minimum of 3.65 to a maximum of 100 percent. 

For a given tax year, SOI's population estimates differ slightly from the actual population of Form 990-T returns that post to the IRS Business Master File during the two-year sampling period. This results from sample code changes and the effects of returns that are “rejected” from the sample as part of the editing process. Examples of returns present on the Master File but rejected from the SOI sample include: those that had gross unrelated business income below the $1,000 filing threshold; were filed for a part-year accounting period, and a full-year return was also filed; were filed for a part-year accounting period that began in a year other than the given tax year; and duplicate filings by a single organization.

The data presented are obtained from returns as originally filed with IRS. In most cases, changes made to the original return because of administrative processing or audit procedures are not captured in the statistics. Changes made based on taxpayer amendment are captured, if available. The data are subjected to comprehensive testing and correction procedures in order to ensure statistical reliability and validity. A general discussion of the reliability of estimates based on samples, methods for evaluating both the magnitude of sampling and non-sampling error, and the precision of sample estimates can be found in the general Appendix of the most recent SOI Bulletin.

 Tax Year

Includes Forms 990-T
processed between:  

 Sample  count

 Population 
count

 Gross Unrelated 
Business Income
(in thousands of dollars)

 1994

Jan. 1, 1995 - Dec. 31, 1996

9,695

36,046

5,379,838

 1995

Jan. 1, 1996 - Dec. 31, 1997

8,108

36,736

6,279,659

 1996

Jan. 1, 1997 - Dec. 31, 1998 

6,777

40,793

7,294,504

 1997

Jan. 1, 1998 - Dec. 31, 1999 

8,064

39,521

7,808,558

 1998

Jan. 1, 1999 - Dec. 31, 2000 

7,609

46,307

7,584,915

1999

Jan. 1, 2000 - Dec. 31, 2001 

7,698

42,279

7,722,135

 2000

Jan. 1, 2001 - Dec. 31, 2002 

7,815

38,839

8,413,385

 2001

Jan. 1, 2002 - Dec. 31, 2003

6,846 

35,672

7,900,464

 2002

Jan. 1, 2003 - Dec. 31, 2004 

6,924

35,236

7,776,017

 2003

Jan. 1, 2004 - Dec. 31, 2005

6,952

36,204

8,436,027

 2004

Jan. 1, 2005 - Dec. 31, 2006 

7,940

38,287

9,492,228

 2005

Jan. 1, 2006 - Dec. 31, 2007 

8,507

40,915

10,849,619

 2006

Jan. 1, 2007 - Dec. 31, 2008 

8,899

43,665

11,271,392

 2007

Jan. 1, 2008 - Dec. 31, 2009 

7,439

45,194

11,682,909

 2008

Jan. 1, 2009 - Dec. 31, 2010 

6,966

42,283

10,300,903

 2009

Jan. 1, 2010 - Dec. 31, 2011 

6,981

42,701

9,700,964