To calculate the growth rates, for example of New York on the following chart:

- Take a screen capture
- Paste it into MSPaint, or similar
- Drag the selection box from one log-axis marker to the next.
- Use MSPaint's ruler indicator (bottom left corner) to see how high the selction is.
- E.g. in the following example, measure from the 1,000 grid line to the 10,000 grid line.
- The distance is
**198 pixels for a 10x multiplication** - Let's call this PixelsPerTenfold
- Pick two date lines around the slope being measured
- Start dragging the selection box from the point where the data line intersects the first date line.
- Drag to a point where the data line intersections the last date line.
- Use the ruler in the corner to measure the vertical distance.
- Call this PixelsIncreased
- In the example below it is
**240 pixels**. - Apply calculations as follows:

PixelsIncreased | = 240 | ||

PixelsPerTenfold | = 198 | ||

Days | = 3 | ||

Daily Multiplier | = 10^{(PixelsIncreased / PixelsPerTenfold / Days)} |
= 2.54 | |

Daily % Increase | = 100 * (DailyMultiplier-1) | = 154% | |

Days to Double | = log_{e}2 / log_{e}DailyMultiplier |
= 0.75 days | |

Days to 10x | = log_{e}10 / log_{e}DailyMultiplier |
= 2.47 days |