How can I obtain slope of a trend line calculated for a time serie

Hi folks,

I wanna obtain the slope of the trend lines which have been calculated for time series. As you can see in the attached plot, there are 3 time serie and trend line has been shown for each one. How can I obtain the slope of each trend line?

Answer 1

[Rafael Hernandez-Walls]

Maybe this is useful for you

https://www.mathworks.com/help/matlab/ref/detrend.html

[Hamed Hedayatnia]

Unfortunately this topic is about calculating and plot the trend, not about determining the slope of the trend.

[Rafael Hernandez-Walls]

then using

polyfit

[Hamed Hedayatnia]

polyfit is not applicable on time series because the x values are dates.

Error using polyval (line 67)

Inputs must be floats, namely single or double.