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 = 0.24, v2 = 9.
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: - 100.
- Choose a random positive number for the end value: 83.
Formula and calculation:
(v1 - v2) / v1 =
(- 100 - 83) / - 100 =
-183 / - 100 =
1.83
Although the absolute difference is negative: -183, the relative decrease change is positive: 1.83. 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:
(0.24 - 9)/|0.24| =
- 8.76/0.24 =
- 8.76 ÷ 0.24 =
- 8.76 ÷ 0.24 × 100/100 =
(- 8.76 × 100 ÷ 0.24)/100 =
(- 876 ÷ 0.24)/100 =
- 3,650/100 =
- 3,650%
The relative percent decrease change
from the original, initial value 0.24 to the final, end value 9:
= - 3,650%
The absolute (actual) difference
0.24 - 9 = - 8.76
By what percentage has 0.24 decreased?
Answer: By - 3,650%
By what percentage is 9 smaller than 0.24?
Answer: By - 3,650%
The relative percent decrease change is negative,
so in this case we really have a relative percent increase instead
(the value goes up).