Financial year | Number of sampled purchase orders | Number of purchase order used to determine Tsc | Percent of total purchase orders (%) |
2012/13 | 156 | 44 | 28.2% |
2013/14 | 213 | 44 | 20.6% |
2014/15 | 215 | 44 | 20.5% |
2015/16 | 141 | 44 | 31.2% |