Why the hell are the fish so big this year?

im happy with it but i just gotta wonder why? like last year i was catching tiny trout under 1lb but this year ive caught 3 rainbows that are about 3lbs in a pond that always has really small fish since its meant for children? and i aint catching anything under 3lbs when i go for rainbow trout this year. and my friend just went fishing today and caught 5 3lb fish in under an hour in a lake known for small ones! the lakes are just recently stocked but whats up with this?