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:
| Polling Firm | Date | PSD - PC | UDMR | Elena Băsescu | Others | Undecided |
| --- | --- | --- | --- | --- | --- | --- |
| Insomar | 26/03-05/04/2009 | 31% | 7% | 6% | 1% | N/A |
| BCS | 6-14/04/2009 | 26,6% | 5,5% | 4,4% | N/A | N/A |
| CURS | 8-16/04/2009 | 30% | 7% | 4% | N/A | N/A |
| CCSB | 18-22/04/2009 | 30% | 5% | 8% | N/A | N/A |
| CSOP | 24-27/04/2009 | 31% | 7% | 4% | 1% | N/A |
| GSS | 3-5/05/2009 | 31.1% | 5.9% | 3% | 3% | N/A |
| Insomar | 30/04-05/05/2009 | 30,9% | 7,9% | 4,2% | N/A | N/A |
| Gallup | 5-9/05/2009 | 31% | 5% | N/A | 2% | N/A |
Question:
What is the psd-pc for 18-22/04/2009?
Answer:
30%