Any takers for what the underlying message of this chart is? How does English compare to the National figures; what about Maths - and how does Maths compare to English?
This is what is affectionately called a spaghetti chart.
Some Excel-fu later:
Following these rules:
  • Dates along the x-axis as categories = bar chart
  • Minimal colours
  • No y-axis scale visible
  • Data labels for values

What can I now "see":
  1. Maths results have been on a 3 year decline (but this probably mirrors the national results)
  2. English 2012, 2013 and 2014 nationally have seen a slight increase, which is not reflected by the local results. Other than the recent 2015 results, 2012,13 and 14 have seen a year on year decline.
  3. The 2015 results for English are an all time high
  4. The 2015 results for Maths are the lowest seen since 2011
Not sure if I could "see" those insights in the original spaghetti chart.