Learn English – Some years on/in

meaningword-choice

It seems both in and on could work for denoting after several years. However, is there any difference between them?

Today, a further six years on, they have hardly changed at all.

and

But five years in, they decided they needed a change.

Best Answer

X years on simply means that we are talking about something that happens five year after an earlier mentioned time.

X years in means that we are X years into something that takes a certain (usually long) time to finish.

On is probably more commonly used, but in the case of projects, programs and other such undertakings, in is used:

The game started all right, but 15 minutes in, the first penalty was given.
The project seemed well-planned, but three months in, the budget needed to be readjusted.