Large Multiplot XY Graph very slow to update visibility/color/line width changes

Question

Hello everyone, 
I have an interesting problem for you all. I am trying to update characteristics of a large XY graph (3600 data points for each of 160 different plot lines, all on one graph) by reference and it's going incredibly slowly.
What I have set up is a system where mousing over certain other indicators and buttons will "highlight" certain groups of plots by making the plot lines a thickness of 2 instead of 1. Similarly, clicking other buttons will change plot colors or toggle visibility of certain plots. To implement this I have a subvi that takes a reference to the xy graph and, in a for loop for each active plot, applies the changes I wish to see made. The problem is that this takes over a minute to complete for just one update!! I'm supposed to be plotting new points every second, and mouseovers and button clicks can happen many times in a second, so this is obviously unacceptable.
I noticed that as I'm looping through all 160 plots in the subvi, the XY graph is updating, one plot at a time. My question is: Is there some way to keep the graph from updating until all the changes have been made? Or maybe some way of applying all the changes at one time, instead of using a for loop?
I have discovered that if I simply drag out a HUGE xy graph property node and do everything all at once instead of in a for loop, the changes appear instantly as desired. Is this really what I have to do to achieve the results I want? It is incredibly time consuming and unmaintainable to have a gigantic property node will all stages of the for loop being applied at once.
Help is greatly appreciated!
-Aaron
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Answer 1

Darin.K wrote:
Two things you can consider:
1) Defer Panel Updates.  Set to True before the Loop and False afterwards.  Speeds things like this up considerably.
2) No way you can see 3600 points on a graph.  With this many plots I would consider decimation of the data to reduce the number of displayed points.
This works amazingly well! In my absolute worst case scenario it takes about 70ms to update all 160 plots for 60 minutes worth of data (3600 points) where as before it took over 240000ms. 70ms is obviously a huge improvement and I thank you very much, this is exactly what I was looking for.
Just as a side note, unfortunately I do have to display up to 3600 points, the end users want to see up to an hours worth of previous data (more even, if possible). Unless you are suggesting I should somehow cut out data, like 4 out of every 5 data points for instance? Part of the problem with cutting out points like that is that there are occasionally spikes in the data that consist of a single point. Cutting out data might remove these which would be a problem. The end users need to be able to spot these spikes when they occur. But perhaps a more complicated decimation that identifies outliers and plots them no matter what to ensure that the spikes remain and only decimate the remaining data? That could get tricky quickly, but doable I suppose. 
Thanks for all the help guys, if anyone has any other methods they think might work as well, I would be interested in trying them too to compare, but Darin's solution will work great.
-Aaron