Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Service | Service ID | Bit rate | Audio channels | Description | Analogue availability |
| --- | --- | --- | --- | --- | --- |
| Capital Yorkshire | C3AA | 128 kbit/s | Joint stereo | Dance and R'n'B | 105.1 MHz (South & West Yorkshire)\n105.6 MHz (Bradford & Sheffield)\n105.8 MHz (Humberside) |
| Choice FM | C0CE | 128 kbit/s | Joint stereo | R'n'B and Hip-hop | — |
| Heart London | CCCD | 128 kbit/s | Joint stereo | Adult contemporary | — |
| Gold | C2CE | 64 kbit/s | Mono LSF | Oldies, 60s, 70s, 80s | — |
| Real Radio (Yorkshire) | C3A4 | 128 kbit/s | Joint stereo | Contemporary | 106.2 MHz (South & West Yorkshire)\n107.6 MHz (Bradford & Halifax)\n107.7 MHz (Sheffield) |
| Real Radio XS | C8C5 | 128 kbit/s | Joint stereo | Classic rock | — |
| UCB Gospel | CED0 | 64 kbit/s | Mono LSF | Christian | — |
| UCB Inspirational | CFD0 | 64 kbit/s | Mono LSF | Christian | — |
| XFM | C0B8 | 128 kbit/s | Joint stereo | Indie / alternative / rock music | — |
| Yorkshire Radio | CFCD | 128 kbit/s | Joint stereo | Pop music and sport | — |
| DAB Guide | E1C000A9 | 8 kbit/s | Data | Hidden service, EPG data | — |
Question:
how many rock stations are listed?
Answer:
2