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 = 870, v2 = 833.7.
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: - 39.
- Choose a random positive number for the end value: 84.
Formula and calculation:
(v1 - v2) / v1 =
(- 39 - 84) / - 39 =
-123 / - 39 ≈
3.153846153846 ≈
3.15
Although the absolute difference is negative: -123, the relative decrease change is positive: 3.15. 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:
(870 - 833.7)/|870| =
36.3/870 =
36.3 ÷ 870 =
36.3 ÷ 870 × 100/100 =
(36.3 × 100 ÷ 870)/100 =
(3,630 ÷ 870)/100 ≈
4.172413793103/100 =
4.172413793103% ≈
4.17%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 870 to the final, end value 833.7:
Rounded off to max. 12 decimal places ≈ 4.172413793103%
Rounded off to max. 2 decimal places ≈ 4.17%
The absolute (actual) difference
870 - 833.7 = 36.3
By what percentage has 870 decreased?
Answer: By ≈ 4.17%
By what percentage is 833.7 smaller than 870?
Answer: By ≈ 4.17%
The relative percent decrease change is positive,
so we really have a relative percent decrease
(the value goes down).