A decline in new user adoption can stem from several factors, such as product-market alignment, obstacles to adoption, and insufficient user engagement. I would start by collecting data through performance metrics like active users, session duration, and churn rate. Next, I would segment the data for more in-depth analysis, potentially categorizing it by demographics, user type, or stages of adoption. Upon identifying the issue, for instance, if product-market alignment is the concern, I might propose adjustments to the product that cater to the needs of the target audience. Alternatively, if obstacles to adoption, such as a complicated signup process, are the problem, I could streamline the user registration process. If user engagement is lacking, I might implement push notifications and incorporate gamification features to re-engage users and enhance retention. These measures should aid in boosting new user adoption, but they need to be consistently evaluated for their effectiveness.