Time
00:00:00    1.000000
00:01:00    1.000000
00:02:00    0.999997
  ...
23:57:00    1.000083
23:58:00    0.999967
23:59:00    0.999864
Name: Last, Length: 1440, dtype: float64

plt.style.use('seaborn-white')
tmp.plot(figsize=(15,7),grid=False,title='Normalized Minute Prices')
plt.xticks(list(range(len(tmp))), tmp.index)
plt.show()