I'm using the "POT" Package in R for fitting a Generalized Pareto distribution to my data. For choosing an approximate threshold I'm using the tcplot() and mrlplot() the following way(x is the data containing vector)

tcplot(x,u.range=c(0,quantile(x,probs=0.995)))
mrlplot(x,u.range=c(0,quantile(x,probs=0.995)),col=c("green","black","green"),nt=200 )

But I get a bit confused sometimes as what point I'll choose as threshold. Particularly as mentioned in this site that "interpretation of these plots often requires a good deal of subjective judgement"

http://www.bioss.ac.uk/people/adam/teaching/OR_EVT/2007/node23.html

For example what would be the threshold given the following plot? 
![A parameter stability and MRL plot][1]


  [1]: https://i.sstatic.net/f3oZh.png