abacus calculation; counting on the abacus
Literal use: performing arithmetic with an abacus. Often implies a meticulous, step-by-step reckoning.
My grandfather still keeps the books using an abacus.
cost-benefit calculation; profit calculation; cold calculation
Figurative use: calculating gains and losses in a detached, often self-interested way. Can carry a negative nuance of being overly mercenary.
His actions are always based on cold calculation.
Don't bring profit-and-loss thinking into friendship.