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:
| Album/Single | Performer | Year | Variant | Notes |
| --- | --- | --- | --- | --- |
| The English and Scottish Popular Ballads vol 3 | Ewan MacColl | 1956 | Gil Morice | The earliest known professional recording (8'37"). |
| Blood and Roses Vol 2 | Ewan MacColl | 1981 | Child Maurice | This is a different version from MacColl's 1956 recording. |
| Right of Passage | Martin Carthy | 1988 | Bill Norrie |  |
| Kornog | Kornog | 2000 | Child Noryce | The only known version by a French band. |
| The Furrowed Field | Damien Barber | 2000 | Bill Norrie |  |
| Songs | Spiers and Boden | 2005 | Child Morris |  |
| At Ruskin Mill | Martin Carthy | 2005 | Bill Norrie | The longest recorded version (9'06"). |
Question:
how many albums are performed by martin carthy or ewan maccoll?
Answer:
4