Maybe he has a basic understanding of time series analysis:<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;File:Vostok_Petit_data.svg" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;File:Vostok_Petit_data.svg</a>