The relative decrease change. Definition:
The relative decrease change is the difference in an indicator over two periods in time, v1 - v2, relative to the value of the indicator in the earlier period, v1.
- Where:
- v1 - is called the reference value (original, initial number);
- v2 - is called the new value (the end value).
- In our case: v1 = 9.23, v2 = 16.
The relative decrease change. Formula:
The relative decrease change =
The actual change / |v1|
(v1 - v2) / |v1| =
- Legend:
- v1 - the original number
- |v1| - the positive value of v1, |v1| >= 0. By example: |10| = 10; |-10| = 10.
- v2 - the new value
- The actual change = v1 - v2
- / - the fraction bar (division)
Why do we use |v1| in the formula instead of v1?
- Let's see what happens if we use v1 instead of |v1|:
- Choose a random negative number as the initial value: - 19.
- Choose a random positive number for the end value: 72.
Formula and calculation:
(v1 - v2) / v1 =
(- 19 - 72) / - 19 =
-91 / - 19 ≈
4.789473684211 ≈
4.79
Although the absolute difference is negative: -91, the relative decrease change is positive: 4.79. By using |v1| instead of v1, the error is corrected.
The relative percent decrease change. Detailed calculations below
By multiplying a number by the fraction 100/100,
we change only the form of the result, not the result.
- 100/100 = 100% = 100 ÷ 100 = 1.
- n × 100/100 = (n × 100)/100 = (n × 100)%, any number.
The relative percent decrease change. Formula:
The relative percent decrease change =
The relative decrease change × 100/100 =
(The relative decrease change × 100)/100 =
(The relative decrease change × 100)%
Calculate the relative percent decrease change:
(9.23 - 16)/|9.23| =
- 6.77/9.23 =
- 6.77 ÷ 9.23 =
- 6.77 ÷ 9.23 × 100/100 =
(- 6.77 × 100 ÷ 9.23)/100 =
(- 677 ÷ 9.23)/100 ≈
- 73.347778981582/100 =
- 73.347778981582% ≈
- 73.35%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 9.23 to the final, end value 16:
Rounded off to max. 12 decimal places ≈ - 73.347778981582%
Rounded off to max. 2 decimal places ≈ - 73.35%
The absolute (actual) difference
9.23 - 16 = - 6.77
By what percentage has 9.23 decreased?
Answer: By ≈ - 73.35%
By what percentage is 16 smaller than 9.23?
Answer: By ≈ - 73.35%
The relative percent decrease change is negative,
so in this case we really have a relative percent increase instead
(the value goes up).