import numpy as np
from matplotlib import pyplot as plt
ys = 200 + np.random.randn(100)
x = [x for x in range(len(ys))]
plt.plot(x,ys,'-')
plt.fill_between(x,ys,195,where=(ys > 195),facecolor='r',alpha=0.6)
plt.title("Fills and Alpha Example")
plt.show()