Hey – great questions, also good to hear that your PA is improving (as a result of your link building efforts, I assume?).
If you're tracking this site as a "campaign" in Moz, then it reports on DA and PA on a month over month basis. It's also not uncommon for a DA to remain stagnant. That said, I have a few caveats in regards to reporting on DA/PA over time:
- "domain authority" and "page authority" are scores developed by Moz and while they're useful for getting a gauge of the quality and quantity of a site's internal link profile, these aren't necessarily ranking factors nor scores that search engine use to rank your site. Moz states on the above link "Domain Authority is not a metric used by Google in determining search rankings and has no effect on the SERPs."
- given that Moz's own calculation of/algorithm for DA and PA change, reporting on DA and PA over time are not reliable metrics for performance.
I'd instead encourage you to evaluate your link building performance by:
- reputation / trust of a given linking domain. Are you earning links from reputable sources with high editorial control, like Business Insider, Time, Forbes, etc?
- referrals from acquired links. Are you actually gaining referral traffic from these links?
- UX metrics of referral traffic. Once referred users land on your site, are they doing/converting/purchasing/etc. the actions you want them to?