By what percent did the ruble fall?

Question

Analytics

Seven years ago, the dollar exchange rate was 23.57 rubles. Now the dollar is worth 65.82. How many percent lost the ruble? If you count according to the formula:
(сегодня * 100 / семь_лет_назад) - 100
It turns out:
(65.82 * 100 / 23.57) - 100 = 179%
But according to the sensations, 23 is "about three times less than 65", and not "a little more than one and a half times" (like 179%). Those. it is more logical to say that the ruble lost 279% of its value:
23.57 * 279% = 65.76
In general, how to correctly calculate how many percent of its value the ruble lost?

Answer 1

Schullz described everything correctly, for example, one conditional iPhone costs 100 dollars and earlier for 6000 rubles you could buy two iPhones (rate 1/30), and now (rate 1/60) - only one, i.e. 50% of what you could have bought before, respectively, a loss of 50%
is another matter, you need to distinguish between "lost in value against the dollar" and "lost in purchasing power", since the loss of the second is usually less, and sometimes much less

Answer 2

There are lies, blatant lies and statistics (c)
Previously, the ruble was worth 1/23.57 = $0.0424
Now the ruble is worth 1/65.82 = $
0.0152 0.0152 is 35.8% of 0.0424
Therefore , the ruble lost 64.2% in value

Answer 3

Do you need a statistical/mathematical answer, or an economic one?
If the latter, then read about the Big Mac index .