Are daily sunspot births correlated?

I am going to present a joint work with professors Jean-Louis Le Mouël (IPGP), Vincent Courtillot (IPGP), and Mikhail Shnirman (IEPT). On the seminar, we will discuss the evolution of quantities (f.e., spectrum and correlation) that explore solar activity on day-to-year scales. We will see that on available intervals of daily data of solar proxies, some of these quantities undergo regime changes prior to a general reconstruction of solar activity. Furthermore, I'll give indirect evidence that sunspot births were positively correlated during the last epoch of high solar activity.