70 Miles After Gas Light Came On

So, my car was on empty, and I needed to get to Jefferson City, MO (87 miles from my house). I only had 10 bucks to put in it, yet it takes 20 round-trip. So, I went, and figured if I ran out of gas coming home, AAA would tow me home for free, because it's within 100 miles of my house. Coming home from Jefferson City, my gas light came on in Freeburg, MO (61 Miles from home). I made it all the way back home with the gas light on. After I'd been home a while, I went to go to Wal-Mart to draw money off of my pay card (I got my pay at 4 in the afternoon). I drove to Wal-Mart (about 3 Miles from my house). I got my money, and headed to McDonald's to grab a burger (forgetting I needed gas, and that's about 2 more miles). I then went through the drive-thru, and then headed to my favorite gas station (which was 4 miles down the road from McDonald's, at least the route I drove.) As soon as I pulled into the station, the car died, and I had to push it to get it by the pump. So right about 70 miles after my gas light came on, my car finally ran out gas. I don't know if God was in a fantastic mood that day or what, but that was definitely a blessing that I was able to drive that far and not have to have my car towed, or push it a few miles. And, just out of curiosity, the next week, I did the exact same thing, just to see for sure why my car would go that far on the light. I made the trip from empty with 10 bucks, and, sure enough, gas light came on in freeburg, made it home, then to walmart, then to mcdonald's, then to the station to get fuel, and it died at the exact same point, right as I pulled into the station. Needless to say, since then, I've lost my job. Nowadays, my car always sits near empty, and I can put 20 bucks in it every 2 weeks, giving me 1/4 of a tank, and by the end of the first week, my light is on, and it still drives about 70 miles. That means, my "empty zone" is equivalent to 1/4 a tank, or in a Contour, 3 gallons.