Using the sorting drop-down on my economy page just now, I stumbled upon this error in the dates, mostly because of the year involved:
Date Range Transaction Credit Debit
2/25/2012 - 2/28/2011 Weekly player salaries $ 404 534
2/28/2011 - 3/14/2011 Weekly player salaries $ 365 892
3/14/2011 - 4/18/2011 Weekly player salaries $ 362 274
4/18/2011 - 1/30/2012 Weekly player salaries $ 0
1/30/2012 - 5/2/2011 Weekly player salaries $ 363 856
5/2/2011 - 7/11/2011 Weekly player salaries $ 359 778
7/11/2011 - 7/25/2011 Weekly player salaries $ 478 829
7/25/2011 - 8/8/2011 Weekly player salaries $ 404 428
8/8/2011 - 9/5/2011 Weekly player salaries $ 401 664
9/5/2011 - 9/12/2011 Weekly player salaries $ 451 484
9/12/2011 - 10/17/2011 Weekly player salaries $ 417 655
10/17/2011 - 10/31/2011 Weekly player salaries $ 487 537
10/31/2011 - 11/14/2011 Weekly player salaries $ 446 147
11/14/2011 - 1/2/2012 Weekly player salaries $ 387 611
1/2/2012 - 2/6/2012 Weekly player salaries $ 420 257
2/6/2012 - 2/13/2012 Weekly player salaries $ 468 917
2/13/2012 - 2/20/2012 Weekly player salaries $ 459 682
The same bug shows up when sorting both by "Player Salaries" as well as "Player Salaries with Transfers." It doesn't appear in any other part of the economy page. What may be at the root of this is that those pages seem to group salaries that don't change over several weeks into one entry; however it's quite impossible that I spent $0 for over eight months as presented above (April 2011-January 2012 line). ;)