Gordon Moore is one of the founders of Intel Corporation. “The number of transistors on an integrated circuit chip doubles every 24 months, that is, it grows exponentially.” Don Valentine, founder of the huge venture fund Sequoia Capital, said: “It's been a pleasure to ride with Moore's Law all these years. It’s easy to underestimate because the power of this law is in its nonlinearity.” If you spent 100 on advertising and earned 110, this is a linear relationship. Then it’s simple: spent 1000 - earned 1100.

Moore's Law works differently, and not everyone understands it. Even after training we are deceived. Five percent per annum will double the capital not in 20 years, but in 14. That is, if wages are not raised for 5 years, with 14% inflation in 5 years we will lose half.

At 20% per annum, we will double not in five, but faster than in 4 years. Now I'll tell you Rule 72: it's the secret way to quickly understand how long it will take to double your capital.

You just need to divide 72 by the expected return. If the return is 6%, we need to divide 72 by 6, and we get 12, that is, with a return of 6% per annum, the capital doubles in 12 years (not quickly, I must admit). For a more accurate result, you need to take 69, but dividing 70 or 72 is more convenient.

70 divides well into 2, 5, 7, 10, 14 and 35 and more or less normally into 20 and 3.5.

69 is divisible by 3 and 23.

72 is divisible by 3, 4, 6, 8, 9, 12, 18, 24, and 4.5 and 16 can also be added here.

It turns out that from two to thirty, almost all the interest rates we have are available. Here you have three percent per year - which means you need 69/3 - 23 years to double. 9% inflation – 72/9 – 8 years to halve the purchasing power of your salary. Simply divide 72 by the rate to get the number of years, or divide by the number of years to get the rate.

Yes, the result is not very accurate. But it is accurate enough to understand what the prospect of the proposal is and immediately give the answer: this suits me.

Well, or not.