title: Alpha vantage AAPL prices do not align with other data sources
body: <p>I'm using the following code to download and plot AAPL daily stock prices:</p>
  
  <pre class="lang-py prettyprint-override"><code>from alpha_vantage.timeseries import TimeSeries
  import matplotlib.pyplot as plt
  
  ts = TimeSeries(key='YOUR_API_KEY', output_format='pandas')
  
  data, meta_data = ts.get_daily(symbol='AAPL', outputsize='full')
  plt.figure(figsize=(10,6))
  
  data['3. low'].plot()
  plt.grid(linestyle='-', linewidth=2)
  plt.title('AAPL stock price daily')
  plt.savefig('sample.png')
  plt.show()
  </code></pre>
  
  <p>This is the plot that I am getting:
  <a href="https://i.stack.imgur.com/hEUsc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hEUsc.png" alt="enter image description here"></a></p>
  
  <p>Obviously, this price drop in 2015 doesn't look right. Also AAPL has never been that expensive. Moreover, this data contradicts with other stock prices sources, e.g. Google.</p>
  
  <p>Am I misusing the API? Is this a bug?</p>