Ethereum earlier ATHs and corrections in 2017.
May 15, 2017 (high - $95) : June 12, 2017 (high - $412)
- up 433% in 28 days
June 12, 2017 (high - $412) : July 16, 2017 (low - $136)
- down 67% in 34 days
July 16, 2017 (low - $136) : September 1, 2017 (high - $395)
- up 290% in 45 days
September 1, 2017 (high - $395) : September 14, 2017 (low - $221)
- down 44% in 13 days
September 14, 2017 (low - $221) : December 18, 2017 (high - $798)
- up 361% in around 95 days
December 18, 2017 (high - $798) : December 22, 2017 (low - $492)
- down 38% in 4 days
December 22, 2017 (low - $492) : January 13, 2018 (high - $1424)
- up 289% in 22 days
January 13, 2018 (high - $1424) : February 4, 2018 (low - $771)
- down 46% in 22 days
From the 2017's trends, Up cycles average 343% and lasts for 48 days. Down cycles average 48.75% and lasts 18 days. Since, 2017 market has changed a lot and it might not follow previous trends at all.
Courtesy: u/vuduchyld