The Republican National Committee's Poll-Watching Army

https://www.snopes.com/fact-check/declaration-of-non-depende...

> Starting in 1987, the I.R.S. required that taxpayers report the Social Security number of all dependents over the age of 5. That year 7 million American children disappeared from the nation's tax returns, representing a 9 percent drop in the 77 million dependents claimed the previous year and $2.9 billion more in yearly tax revenue. The tax agency said about 20 percent of the vanished dependents were children who had been claimed as dependents by both parents after a divorce. Under the law, only one parent may claim the child as a deduction