CREATE TABLE table_10824 ("Year" FLOAT, "Artist" TEXT, "Mintage  ( Proof ) " TEXT, "Issue Price  ( Proof ) " TEXT, "Mintage  ( BU ) [ clarification needed ]" TEXT, "Issue Price  ( BU ) [ clarification needed ]" TEXT)

What's the average Year with an Issue Price (Proof) of $49.95, and Artist of W.H.J. Blakemore?
SELECT AVG("Year") FROM table_10824 WHERE "Issue Price (Proof)" = '$49.95' AND "Artist" = 'w.h.j. blakemore'
SELECT AVG("Year") FROM "table_10824" WHERE "Artist" = 'w.h.j. blakemore' AND "Issue Price (Proof)" = '$49.95'