# Rate of Change & Rate of Change Percent

**Rate of Change** is simply the net change in Price over the selected period. The **Rate of Change Percent** reflects the same reading on a percentage basis. Considered a measurement of momentum since it is the speed at which price changes over a specific period of time.

ROC |
`C - Cx` |
`x` =Period |

ROC% |
`100 * (C / Cx - 1)` |

Where `x`

is the period which must be an integer.

### Examples

A 50 period rate of change can be written as follows.

`C - C50`

A 50 period rate of change percent can be written as follows.

`100 * (C / C50 - 1)`

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