UK power outage August 2019

Suggestions have been made that adding  wind energy to the UK national grid has increased the frequency variability.

By looking at the Gridwatch data for frequency it is possible to see the frequency variation at a 5 minute sample rate.

I have plotted the  frequency for 2012 to 2019 looking at the rolling
 [50 minute max]-[50 minute min]
data.

This shows an insignificant change over the 7 years:

However looking at frequency deviations above 0.5Hz there were none before 2005 but 6 after 2005.

Also looking at the overall plot there appears to have been an improvement in frequency stability at March 2014. If this is true then the plot does show a worsening of frequency stability from 2014 until about 2017

Since 2017 there has been insignificant change.