I have a model dataset that has a maximum value of (approx.) 10,000 or 1e4.
When I plot this with MPL some of the timeseries come out with a wrong axis. As you can see in the attached figure, the maximum appears to be 2.0e4.
One timeseries exhibits the value 7.0e3 (shown in Figure, not example).

Minimal example attached (needs text files).

MPL version 1.5.3, Python 3.5.2, both installed from anaconda
Mac OSX 10.11.6

y0.txt
y1.txt
y2.txt
y3.txt
y4.txt
y5.txt
y6.txt
y7.txt
y8.txt
y9.txt

example.py.txt