Six distinct colours are used to represent the possible victorious parties in 705 consistent constituencies over ten elections on the (changing) equal electorate cartograms (Appendices B and C) — software written by author on an Archimedes computer.
Notice how the overall shape of the country has changed in terms of adult population over the last forty years. The highlands have lost people while the south of the country has grown. How different the picture of 1987 is to 1955 — the basic regional pattern remains but is very much more intense today — a sharper geography. The position of Northern Ireland has, of course, changed dramatically.