Accepted answer

The value you are referencing, i.e. live php page, seems to be 1.x and increasing very slowly. (1.7 while I was looking).

In your parsing you do the following:

y = parseInt(localStorage.getItem("data"));

And since the value is 1.7, and you try to parse it as an integer with parseInt, it gets converted to 1. Using parseFloat will give you a slowly increasing graph.

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