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:
| Scheme | Tariff code | BTs retail price (regulated) | Approx premium | Prefixes |
| --- | --- | --- | --- | --- |
| Pence per call, fixed at all times | ff15 | 5.10p/call | 7p/call | 0871, 0872 |
| Pence per call, fixed at all times | ff28 NTS | 8.50p/call | 10p/call | 0871, 0872 |
| Pence per call, fixed at all times | ff0 PRS | 8.60p/call | 10p/call | 0871, 0872 |
| Pence per minute, fixed at all times | g21 | geographic rate or inclusive | nil | 030, 033, 034, 037 |
| Pence per minute, fixed at all times | g22 | 0.425p/min | 2p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g8 | 0.851p/min | 2p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g27 | 1.277p/min | 3p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g9 | 1.702p/min | 4p/min | 0843, 0844 |
| Pence per minute, fixed at all times | (no code) | 2p/min or inclusive | 2p/min | 0845 only |
| Pence per minute, fixed at all times | g28 | 2.128p/min | 3p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g10 | 2.553p/min | 4p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g11 | 3.404p/min | 5p/min | 0843, 0844 |
| Pence per minute, fixed at all times | g6 and p27 | 4.255p/min | 7p/min | 0843, 0844, 0871, 0872 |
| Pence per minute, fixed at all times | (no code) | 8p/min or inclusive | ~10p/min 0p/min | 0870 only |
Question:
How many tariff codes have a bts retail price of 2.553p/min?
Answer:
1.0