find the percent of change from 13 to 26

How to deal with Zeros when calculating percentage changes is the research worker's call and requires some domain expertise. If the researcher believes that IT would not glucinium distorting the data, s/he may merely add a very small constant to all values to eliminate all zeros. In business enterprise series, when dealing with trading volume, for exemplar, we may not want to bash this because trading bulk = 0 scarce means that: the plus did not sell at all. The meaning of volume = 0 May be very different from intensity = 0.00000000001. This is my preferred strategy in cases whereby I can not logically add a small constant to entirely values. Moot the percentage change formula ((New-Nonmodern)/Old) *100. If New = 0, past percentage change would be -100%. This total indeed makes financial sense as long as information technology is the minimum percentage change in the series (This is indeed guaranteed to be the minimum percentage change in the serial). Why? Because information technology shows that trading book experiences maximum feasible decrease, which is going from any number to 0, -100%. So, I'll be fine with this assess beingness in my percentage change series. If I renormalize that series, then evening better since this (perhaps) comparatively big number in direct value will embody analyzed on the same scale as other variables are. Now, what if the Honest-to-god value = 0. That's a trickier caseful. Percentage change due to going from 0 to 1 will be equal thereto cod to going from 0 to a million: eternity. The fact that we call both "eternity" percentage change is difficult. In that case, I would set the infinities equal to np.nan and interpolate them.

The following graph shows what I discussed above. Protrusive from series 1, we get series 4, which is ready to represent analyzed, with no Inf or NaNs.

One more thing: a lot of the fourth dimension, the conclude for calculating percentage change is to stationarize the data. And so, if your original series contains zero and you wish to convert it to percentage convert to achieve stationarity, first make a point information technology is non already stationary. Because if it is, you don't wealthy person to calculate percentage change. The point is that series that take the value of 0 a lot (the problem OP has) are very likely to be already stationary, for example the mass serial I considered higher up. Imagine a series periodical to a higher place and below zero, thus hitting 0 at multiplication. Such a series is very likely already stationary.

find the percent of change from 13 to 26

Source: https://stackoverflow.com/questions/19908431/how-to-calculate-percentage-when-old-value-is-zero/48735491