| | 2017 | 2016 | 2015 | 2014 | 2013 |
Unit sales | | 16,043 | 15,171 | 14,572 | 13,509 | 11,528 |
Revenue | | £3,422.3m | £3,136.8m | £2,901.7m | £2,573.9m | £2,085.9m |
Average selling price | | £213,321 | £206,765 | £199,127 | £190,533 | £180,941 |
Profit from operations | | £966.1m | £778.5m | £634.5m | £473.3m | £333.1m |
Profit before tax | | £977.1m | £782.8m | £637.8m | £475.0m | £329.6m |
Basic earnings per share | | 258.6p | 205.6p | 173.0p | 124.5p | 83.3p |
Diluted earnings per share | | 246.5p | 199.5p | 169.1p | 124.3p | 82.8p |
Cash return/dividend per share | | 235.0p | 135.0p | 110.0p | 95.0p | 70.0p |
Net assets per share | | 1,036.6p | 887.3p | 800.7p | 715.4p | 671.4p |
Total shareholders' equity | | £3,201.6m | £2,737.4m | £2,455.8m | £2,192.6m | £2,045.5m |
Return on capital employed | | 51.5% | 39.4% | 32.1% | 24.6% | 17.6% |
All figures stated before exceptional items and goodwill impairment where applicable.