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:
| School | Location | Outright Titles | Shared Titles | Runners-Up | Total Finals | Last Title | Last Final |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Methodist College Belfast | Belfast | 35 | 2 | 25 | 62 | 2014 | 2014 |
| Royal Belfast Academical Institution | Belfast | 29 | 4 | 21 | 54 | 2007 | 2013 |
| Campbell College | Belfast | 23 | 4 | 12 | 39 | 2011 | 2011 |
| Coleraine Academical Institution | Coleraine | 9 | 0 | 24 | 33 | 1992 | 1998 |
| The Royal School, Armagh | Armagh | 9 | 0 | 3 | 12 | 2004 | 2004 |
| Portora Royal School | Enniskillen | 6 | 1 | 5 | 12 | 1942 | 1942 |
| Bangor Grammar School | Bangor | 5 | 0 | 4 | 9 | 1988 | 1995 |
| Ballymena Academy | Ballymena | 3 | 0 | 6 | 9 | 2010 | 2010 |
| Rainey Endowed School | Magherafelt | 2 | 1 | 2 | 5 | 1982 | 1982 |
| Foyle College | Londonderry | 2 | 0 | 4 | 6 | 1915 | 1915 |
| Belfast Royal Academy | Belfast | 1 | 3 | 5 | 9 | 1997 | 2010 |
| Regent House Grammar School | Newtownards | 1 | 1 | 2 | 4 | 1996 | 2008 |
| Royal School Dungannon | Dungannon | 1 | 0 | 4 | 5 | 1907 | 1975 |
| Annadale Grammar School (now Wellington College) | Belfast | 1 | 0 | 1 | 2 | 1958 | 1978 |
| Ballyclare High School | Ballyclare | 1 | 0 | 1 | 2 | 1973 | 2012 |
| Belfast Boys' Model School | Belfast | 1 | 0 | 0 | 1 | 1971 | 1971 |
| Grosvenor High School | Belfast | 1 | 0 | 0 | 1 | 1983 | 1983 |
| Wallace High School | Lisburn | 0 | 0 | 4 | 4 | N/A | 2007 |
| Derry Academy | Derry | 0 | 0 | 2 | 2 | N/A | 1896 |
| Dalriada School | Ballymoney | 0 | 0 | 1 | 1 | N/A | 1993 |
| Galway Grammar School | Galway | 0 | 0 | 1 | 1 | N/A | 1887 |
| Lurgan College | Lurgan | 0 | 0 | 1 | 1 | N/A | 1934 |
| Omagh Academy | Omagh | 0 | 0 | 1 | 1 | N/A | 1985 |
| Sullivan Upper School | Holywood | 0 | 0 | 1 | 1 | N/A | 2014 |
Question:
what is the difference in runners-up from coleraine academical institution and royal school dungannon?
Answer:
20