Southee hasn't been able to reach the level he was at two years ago, but has shown signs he was on his way back to that level in recent times.
"I had a couple of injuries over the summer, didn't play a lot of cricket," he said.
"Couple of poor test matches. Found in South Africa and Zimbabwe that I was bowling a lot better than in Australia, even though I wasn't getting the wickets."
Now sitting on the sidelines injured, Southee has been able to get a bit of perspective on his form over the last year.
"This setback isn't ideal but I'll keep working hard to get back to where I was a year ago.
"At the end of the day, if you're not taking wickets, you aren't doing your job and you can't help but look at the stats."
Southee hasn't been alone in his struggles. Fellow opener Trent Boult has been below his best, averaging just under 37 for his 19 wickets this year.
Southee said they realise they need to be better to help the team
"As a pair, Trent and I haven't been at that level we were for a while. We've shown glimpses but we are a better side when we are both firing and taking wickets," he said.
"It's frustrating."
Southee will rejoin the Black Caps for the One Day International leg of the Indian tour.