Opening Black Bolt Pokemon Center Elite Trainer Box (Exclusive) returns about $75.42 in card value against its $271.05 price — roughly $0.28 back per dollar spent. On current prices, you lose money on average by opening it.
See every card and pull rate in Black Bolt
How expected value is calculated — card value only, from published pull rates and daily market prices.
Black Bolt Pokemon Center Elite Trainer Box (Exclusive) on TCGplayer