9. Other information by nature

The income statement includes personnel costs for €52,815 thousand in 2014 (€13,482 thousand in 2013) and they consist of the following:

(€ thousand)20142013
Wages and salaries 36,580 7,488
Defined contribution plans 3,291 128
Social security costs 5,719 2,660
Other personnel costs 7,225 3,206
Total personnel costs 52,815 13,482

An analysis of the average number of employees by category is as follows:

 20142013
Managers 47 33
White-collar 356 52
Blue-collar 588 -
Average number of employees 991 85

None of these employees are based in The Netherlands. Some of the Company’s managers carried out their activities at the principal subsidiaries of the Group and the associated costs were charged back to the legal entities concerned.