TITLE: Interpolation

<li>Non-linear timeline problem
  <ul>
  <li>Sample time provided in decimal years
  <li>1 day in a normal year = 0.0027397
  <li>1 day in a leap year = 0.0027322
  <li>Rounding errors at year changes
  </ul>

<li>Solution: Convert to truncated Julian days format
  <ul>
  <li>Integer day counting system
  <li>Julian days: starts 1 January 4713 BC
  <li>To get higher precision we started 1 January 1900
  <li>Converted to Julian days for interpolation
  <li>Converted back to decimal years to get output
  </ul>