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:
| Date(s) conducted | Polling organisation/client | Cons | Plaid Cymru | Lib Dem | Others | Lead |
| --- | --- | --- | --- | --- | --- | --- |
| 5 May 2011 | Welsh Assembly election results, 2011 | 25.0% | 19.3% | 10.6% | 2.8% | 17.3% |
| 4 May 2011 | YouGov/ITV Wales | 20% | 18% | 9% | 6% | 29% |
| 2 May 2011 | YouGov/ITV Wales | 21% | 18% | 8% | 7% | 27% |
| 14 April 2011 | YouGov/ITV Wales | 20% | 17% | 8% | 6% | 32% |
| 7 April 2011 | rmg:Clarity/Western Mail | 20% | 17% | 8% | 5% | 34% |
| 30 March 2011 | YouGov/ITV Wales | 21% | 17% | 8% | 6% | 30% |
| 8 March 2011 | YouGov/ITV Wales | 20% | 19% | 7% | 7% | 29% |
| 26 January 2011 | YouGov/ITV Wales | 21% | 21% | 7% | 6% | 24% |
| 22 December 2010 | YouGov/ITV Wales | 23% | 21% | 6% | 6% | 23% |
| 24 November 2010 | YouGov/ITV Wales | 21% | 21% | 9% | 6% | 23% |
| 27 November 2010 | YouGov/ITV Wales | 19% | 21% | 9% | 8% | 23% |
| 3 May 2007 | National Assembly for Wales election, 2007 | 22.4% | 22.4% | 14.8% | 8.2% | 9.8% |
Question:
I want the plaid cymru for Polling organisation/client of yougov/itv wales for 4 may 2011
Answer:
18%