Opening Celestial Storm Single Pack Blister [Tapu Fini] returns about $15.28 in card value against its $89.99 price — roughly $0.17 back per dollar spent. On current prices, you lose money on average by opening it.
See every card and pull rate in SM - Celestial Storm
How expected value is calculated — card value only, from published pull rates and daily market prices.
Celestial Storm Single Pack Blister [Tapu Fini] on TCGplayer