If we ignore a few bumps with time scales of a decade or so, the curve is surprisingly well fit by a pure exponential. (science.sciencemag.org)
Deep steric changes occur over time scales of decades or longer and aren't expected to explain the discrepancy over the last 5 years (Antonov 2005). (skepticalscience.com)
On short time scales of decades to a few centuries this is not possible, as the solar influence clearly dominates the production signal (e.g., Snowball & Muscheler 2007) and local climate can also play a role (e.g., Usoskin et al. 2009). (swsc-journal.org)