CREATE TABLE table_74658 ("Party" TEXT, "Seats" TEXT, "Net gain/loss" TEXT, "% of seats" TEXT, "% of votes" TEXT)

When there was a net gain/loss of +34, what was the percentage of seats that party held?
SELECT "% of seats" FROM table_74658 WHERE "Net gain/loss" = '+34'
SELECT "% of seats" FROM "table_74658" WHERE "Net gain/loss" = '+34'