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 = 356, v2 = 27.6.
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: - 79.
- Choose a random positive number for the end value: 63.
Formula and calculation:
(v1 - v2) / v1 =
(- 79 - 63) / - 79 =
-142 / - 79 ≈
1.79746835443 ≈
1.8
Although the absolute difference is negative: -142, the relative decrease change is positive: 1.8. 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:
(356 - 27.6)/|356| =
328.4/356 =
328.4 ÷ 356 =
328.4 ÷ 356 × 100/100 =
(328.4 × 100 ÷ 356)/100 =
(32,840 ÷ 356)/100 ≈
92.247191011236/100 =
92.247191011236% ≈
92.25%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 356 to the final, end value 27.6:
Rounded off to max. 12 decimal places ≈ 92.247191011236%
Rounded off to max. 2 decimal places ≈ 92.25%
The absolute (actual) difference
356 - 27.6 = 328.4
By what percentage has 356 decreased?
Answer: By ≈ 92.25%
By what percentage is 27.6 smaller than 356?
Answer: By ≈ 92.25%
The relative percent decrease change is positive,
so we really have a relative percent decrease
(the value goes down).