| 2014 | 2015 | 2016 | 2017 | 2018 |
Total R&D investment (RMB 100 million) | 36.80 | 36.75 | 45.22 | 62.66 | 85.36 |
R & D investment-Automobile (RMB 100 million) | 24.66 | 22.62 | 28.12 | 41.64 | 50.82 |
Proportion of automobile R&D investment in total R&D investment (%) | 67.01 | 61.53 | 62.19 | 66.45 | 60.54 |
Proportion of R&D investment in operating income (%) | 6.32 | 4.59 | 4.37 | 5.92 | 6.56 |
Proportion of R&D investment in operating income (automobile) (%) | 9.10 | 5.56 | 4.93 | 7.35 | 6.69 |