| | 2018 | 2017 |
Theoretical rent | 55,457 | 52,954 |
Incentives | (1,502) | (1,207) |
Vacancies | (2,654) | (2,337) |
Total gross rental income | 51,301 | 49,410 |
The future contractual rent from leases in existence on 31 December 2018, until the end of the contract (accounted for on the basis of the minimum rent) can be analysed as follows:
| | 2018 | 2017 |
First year | 54,716 | 51,716 |
Second to fifth years | 151,493 | 148,387 |
More than five years | 155,157 | 144,319 |
Service charge income represents € 2.1 million (2017: € 1.9 million) income receivable from tenants for the services utilities, caretakers, etc. when the Fund acts as a principal.