CREATE TABLE table_name_70 (upper_index_mj__nm_3 INT, upper_index_kcal__nm_3 VARCHAR)

What is the average upper index MJ/Nm 3 for the upper index Kcal/Nm 3 entry of 19,376?
SELECT AVG(upper_index_mj__nm_3) FROM table_name_70 WHERE upper_index_kcal__nm_3 = 19 OFFSET 376
SELECT AVG("upper_index_mj__nm_3") FROM "table_name_70" WHERE "upper_index_kcal__nm_3" = 19 OFFSET 376