The quant firm Optimer was able to outperform its competitor using an investment model based on both size and BE$-$ME ratio. Optimer continues to refine its model to try to boost returns further. Specifically, it creates a proprietary index of climate risk exposure that is measured by combining data on the distance between a firm's headquarters location and the seashore, the impact of energy prices on a firm's profits, and the perceived sustainability a firm's products.

Optimer sorts all firms into $5$ portfolios based on values of this index, and finds high$-$climate risk firms outperform low$-$climate risk firms since $2000($see below table$).$ Is this evidence sufficient to conclude that climate risk is a priced factor since the $2000$s$?$ If yes, briefly explain why. If no$,$ briefly state how the table could be modified to provide better evidence?

$|$Portfolio$\backslash$Decade $|1980$s $|1990$s $|2000$s $|2010$s $|$

$|$:$------------------------|$:$-----$:$|$:$-----$:$|$:$-----$:$|$:$-----$:$|$

$|1(=$ Lowest Climate Risk$)|-1\mathrm{.}5\%|3\mathrm{.}8\%|-2\mathrm{.}7\%|4\mathrm{.}5\%|$

$|2|7\mathrm{.}7\%|5\mathrm{.}2\%|3\mathrm{.}5\%|6\mathrm{.}8\%|$

$|3|-3\mathrm{.}6\%|4\mathrm{.}3\%|6\mathrm{.}2\%|9\mathrm{.}7\%|$

$|4|4\mathrm{.}1\%|6\mathrm{.}1\%|7\mathrm{.}5\%|11\mathrm{.}3\%|$

$|5(=$ Highest Climate Risk$)|5\mathrm{.}3\%|5\mathrm{.}6\%|12\mathrm{.}9\%|13\mathrm{.}8\%|$