Fiona has decided to undergo some exercise training to try and get fitter.  She has heard that mitochondria are the power houses of cells, and you can make more of these if you train hard.  Fiona would like to know how many mitochondria she has, but that would mean having a muscle biopsy and not a feasible option.  After some investigations, Fiona learnt that it is also possible to undertake a maximal exercise test on an exercise bike that would provide some measure of her fitness, in units of maximal oxygen consumption or a VO₂ peak test.  She found someone to do this testing and did the first test before beginning any training, at which point her VO₂ peak was 31 ml.kg^-1.min^-1.   She underwent the same test at the end of a 12 week training regime, when her VO₂ peak was 39 ml.kg^-1.min^-1. 

Based on this information, what percent improvement in VO₂ peak did Fiona achieve? (enter value only to one decimal place)