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:
| No. | Name | Term of office | Term of office | Political party | Ministry |
| --- | --- | --- | --- | --- | --- |
| 1 | C. D. Howe | November 2, 1936 | July 8, 1940 | Liberal | 16 (King) |
| 2 | Arthur Cardin | July 8, 1940 | May 13, 1942 | Liberal | 16 (King) |
| – | C. D. Howe (acting) | May 13, 1942 | October 6, 1942 | Liberal | 16 (King) |
| 3 | Joseph-Enoil Michaud | October 6, 1942 | April 18, 1945 | Liberal | 16 (King) |
| 4 | Lionel Chevrier | April 18, 1945 | July 1, 1954 | Liberal | 17 (St. Laurent) |
| 5 | George Carlyle Marler | July 1, 1954 | June 21, 1957 | Liberal | 17 (St. Laurent) |
| 6 | George Hees | June 21, 1957 | October 11, 1960 | Progressive Conservative | 18 (Diefenbaker) |
| 7 | Léon Balcer | October 11, 1960 | April 22, 1963 | Progressive Conservative | 18 (Diefenbaker) |
| 8 | George McIlraith | April 22, 1963 | February 3, 1964 | Liberal | 19 (Pearson) |
| 9 | Jack Pickersgill | February 3, 1964 | September 19, 1967 | Liberal | 19 (Pearson) |
| 10 | Paul Hellyer | September 19, 1967 | April 20, 1968 | Liberal | 19 (Pearson) |
| 10 | Paul Hellyer | April 20, 1968 | April 30, 1969 | Liberal | 20 (Trudeau) |
| – | James Armstrong Richardson (acting) | April 30, 1969 | May 5, 1969 | Liberal | 20 (Trudeau) |
| 11 | Don Jamieson | May 5, 1969 | November 27, 1972 | Liberal | 20 (Trudeau) |
| 12 | Jean Marchand | November 27, 1972 | September 26, 1975 | Liberal | 20 (Trudeau) |
| 13 | Otto Lang | September 26, 1975 | June 4, 1979 | Liberal | 20 (Trudeau) |
| 14 | Don Mazankowski | June 4, 1979 | March 3, 1980 | Progressive Conservative | 21 (Clark) |
| 15 | Jean-Luc Pépin | March 3, 1980 | August 12, 1983 | Liberal | 22 (Trudeau) |
| 16 | Lloyd Axworthy | August 12, 1983 | June 29, 1984 | Liberal | 22 (Trudeau) |
| 16 | Lloyd Axworthy | June 30, 1984 | September 16, 1984 | Liberal | 23 (Turner) |
| (14) | Don Mazankowski (2nd time) | September 17, 1984 | June 29, 1986 | Progressive Conservative | 24 (Mulroney) |
| 17 | John Crosbie | June 30, 1986 | March 30, 1988 | Progressive Conservative | 24 (Mulroney) |
| 18 | Benoît Bouchard | March 31, 1988 | February 22, 1990 | Progressive Conservative | 24 (Mulroney) |
| 19 | Doug Lewis | February 23, 1990 | April 20, 1991 | Progressive Conservative | 24 (Mulroney) |
| 20 | Jean Corbeil | April 21, 1991 | June 24, 1993 | Progressive Conservative | 24 (Mulroney) |
| 20 | Jean Corbeil | June 25, 1993 | November 3, 1993 | Progressive Conservative | 25 (Campbell) |
| 21 | Doug Young | November 4, 1993 | January 24, 1996 | Liberal | 26 (Chrétien) |
| 22 | David Anderson | January 25, 1996 | June 10, 1997 | Liberal | 26 (Chrétien) |
| 23 | David Collenette | June 11, 1997 | December 11, 2003 | Liberal | 26 (Chrétien) |
| 24 | Tony Valeri | December 12, 2003 | July 19, 2004 | Liberal | 27 (Martin) |
| 25 | Jean Lapierre | July 20, 2004 | February 5, 2006 | Liberal | 27 (Martin) |
| 26 | Lawrence Cannon | February 6, 2006 | October 29, 2008 | Conservative | 28 (Harper) |
| 27 | John Baird | October 30, 2008 | August 6, 2010 | Conservative | 28 (Harper) |
| 28 | Chuck Strahl | August 6, 2010 | May 18, 2011 | Conservative | 28 (Harper) |
| 29 | Denis Lebel | May 18, 2011 | July 15, 2013 | Conservative | 28 (Harper) |
| 30 | Lisa Raitt | July 15, 2013 | Incumbent | Conservative | 28 (Harper) |
Question:
how many ministers of transport were members of the liberal party?
Answer:
20