CREATE TABLE table_34963 ("Eruptions" TEXT, "Country" TEXT, "Location" TEXT, "Year" FLOAT, "Volcanic Explosivity Index" TEXT, "Fatalities" TEXT)

How many years have a Location of pacific ring of fire, and Eruptions of pinatubo?
SELECT SUM("Year") FROM table_34963 WHERE "Location" = 'pacific ring of fire' AND "Eruptions" = 'pinatubo'
SELECT SUM("Year") FROM "table_34963" WHERE "Eruptions" = 'pinatubo' AND "Location" = 'pacific ring of fire'