The Internal Revenue Service says the number of Iowans filing their federal tax returns electronically has already increased over last year.I-R-S spokesperson Donna Migazzi (mah-GAH’-zee) says nearly 58-percent of the Iowa returns already in were filed electronically. Migazzi says filing electronically allows you to get your refund quicker, and it helps avoid costly errors.The error rate for electronic filing is less than one percent compared to 20-percent for paper filing. She says some Iowans may qualify for free electronic filing.Migazzi says the early returns show Iowans getting more money back due to increased tax credits.April 15th is the deadline for filing your federal tax return.