title: Highstock not displaying year on tooltip
body: <p>Instead of showing the year in the tooltip, my highstock graph is showing time. It seems that my options are set the same as the demo, does anyone know why this may be happening? </p>
  
  <p>This is my tooltip: 
  <a href="https://i.stack.imgur.com/zjjvm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zjjvm.png" alt="enter image description here"></a></p>
  
  <p>This is what I want it to look like: <a href="https://i.stack.imgur.com/613Un.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/613Un.png" alt="enter image description here"></a></p>