Math might be most people’s least favorite subject but it’s an essential one. Without it, we wouldn’t be able to enjoy our modern technologies. That’s why calculations need to be precise, and most of the time, it’s the smallest miscalculation that throws everything off. NASA project failures, heavy submarines and inflated housing benefits are among some of things that have gone insanely wrong because of these minor mistakes. Here are five such examples.

1. Bank Of America’s Dividend Payments And Stock Buybacks

In 2014, Bank of America underwent a regular stress test to determine if they were healthy enough to overcome a financial crisis or recession. The bank successfully passed it and happily told shareholders that they were going to pay dividends and buy back $4 billion worth of stock. But they didn’t actually pass it and only believed this because of a mistake in determining the values of some bonds owned by one of its subsidiaries. As you could imagine the shareholders were furious and the bank’s stocks plummeted by five percent or $9 million.

2. Spain’s S-80 Submarine Program

If you know anything about decimals, it’s that putting the decimal point in the wrong place changes everything. The Spanish navy learned that the hard way in 2003 when they spent $2.7 billion on a S-80 submarine program to build four diesel-electric submarines. Ten years after completing one of them, it was discovered that the submarine was 70 tons heavier than it was supposed to be. This made it difficult for the submarine to resurface, if it ever went underwater. The country then had to spend an additional $14 million to reduce the weight of the remaining submarines.

3. Ariane 5 Rocket Explosion

On June 4, 1996, the European Space Agency launched their Ariane 5 rocket. Just thirty-seven seconds into takeoff, the $370 million rocket, as well as the four satellites onboard exploded into smithereens. Ground control blew it up themselves due to the rocket going haywire because of a mathematical error called an integer overflow. See, the Ariane 5 ran on the same software as the Ariane 4. But the Ariane 5 was faster than the Ariane 4 and faster meant larger figures. The old software was unable to handle the larger readings, and well, you know the rest.

4. The Amsterdam City Council’s €188 Million Housing Benefits Error

December 2013 was a great time for the poor families in Amsterdam. The city distributed €188 million among 10,000 families, with some receiving €15,500 and others €34,000. But their happiness and celebrations were short-lived because of a glitch in the city’s payment software. The budget was actually supposed to be €1.8 million not €188 million. So that €15,500 was supposed to be €155, and €340 instead of €34,000. Luckily, they were able to retrieve most of the money back, except for a whopping €2.4 million.

5. Mars Climate Orbiter Crash

Here’s another failed space project for you. In 1999, a simple conversion error caused NASA’s Mars Climate Orbiter to crash into the red planet. In fact, it was one of the agency’s most embarrassing moments. NASA engineers completely missed the fact that Lockheed Martin used the imperial system while they continued using the metric system. For nine whole months no one picked up on the mistake, not until they lost contact with the orbiter. And just like that, $125 million was gone.