Today is tax day, the day when individual e tax returns are due to the federal government. Here are seven figures you should know about tax day:

1. The average federal tax rate for all households (tax liabilities divided by e, including government transfer payments) before taxes is 18.1 percent.

2. Households in the top quintile (including the top percentile) paid 68.8 percent of all federal taxes, households in the middle quintile paid 9.1 percent, and those in the bottom quintile paid 0.4 percent of federal taxes. (Quintiles — fifths — contain equal numbers of people.)

3. Social insurance taxes (e.g., Social Security, Medicare) account for the largest share of taxes paid by households in all but the top quintile.

4. The U.S. tax code is approximately 2,600 pages long (about 1.5 times longer than Tolstoy’s War and Peace and 2.5 times longer than Ayn Rand’s Atlas Shrugged).

5. At midnight, the U.S. Treasury gets an extra $760 million. Taxpayers have three years to claim refunds, so the $760 million that is owed to 918,600 people will, by statute, go to the governments coffers tomorrow.

6. If you’re owed a refund, you won’t get in trouble if you miss the April 15 filing deadline. But if you’re wrong and you actually owe money, you’ll incur a maximum penalty of 5% for each month after the deadline. If you’re more than 60 days late, you’ll be fined $135, or 100% of the unpaid tax — whichever amount is smaller.

7. Examining 30 years of road crash data from the National Highway Traffic Safety Administration, researchers found that fatal car crashes increase 6 percent on April 15.