Map Legend Issues - Incorrect order in bubbles

Hi,

I have created a Map visualisation using local areas (Burton on Trent, Derby, Lichfield etc.) and how many referrals our Trust has received from each area. I have also added a legend for financial year, so I can compare referrals received during the same period in the previous financial year. The only issue I have is that 201617 financial year is displaying on the right hand side of the bubbles rather than the left (I want it on the left as obviously 201617 is prior to current financial year). I have tried creating a Fin_YearNo column and ordering my financial year on this however this has no affect.

Strangley the legend labels at the top of the visualisation are in the correct order (201617 then 201718) however not in the bubbles within the map.

Does anyone know if you can change the order of bubble sections within a map?