Ah ok, Focus.

Like you've already noticed, there's usually a dozen of different spring sets for modern Ford cars. For different overall car weights as estates are usually heavier, especially on the rear axle, different extras or different engines (weight and therefore weight distribution) AND for "sports" and non-sports vehicles, some came with lowering springs. Maybe you've got a car with a light engine and lower sports suspension and put in a set of (very cheap aftermarket) springs for a car with a 2,0 TDCI and standard ride height.

Do you still have your old springs?