Unlocking Sustainable Growth: How Local News Publishers Can Use Mather’s Subscription Proficiency Index (SPI) to Scale Digital Subscriptions

By: Pete Doucette, Senior Managing Director, Consulting at Mather

July 15th, 2025

Mather works with hundreds of local news publishers around the globe with regard to digital transformation. As part of this advisory work, I am almost always asked some combination of the following questions:

• We are trying to scale digital subscriptions…what are the most important metrics we should be focused on?
• How does our digital subscription performance compare with other publishers? Are we doing better or worse?
• Are we where we should be based on our digital subscription maturity?
• How do metrics like conversion and churn work in combination with each other? Is there a way to balance competing metrics?

Mather has created the Subscription Proficiency Index (SPI) to answer these and other related questions and help publishers scale their digital subscriptions and revenue.

What Is It?

SPI is a scoring system that evaluates a publisher’s digital subscription performance across key growth levers, providing clear, data-driven insights.

How SPI Helps Publishers

The SPI helps teams prioritize resources, enhance subscription strategies, and fine-tune their business model for long-term, sustainable growth by pinpointing performance gaps and highlighting improvement opportunities. The SPI comprises six key variables representing the potential growth levers.

1. Audience Growth (AG)
2. Audience Engagement (AE)
3. Conversion Effectiveness (CE)
4. Churn Mitigation (CM)
5. Average Revenue per User (AR)
6. Subscriber Penetration (SP)

The SPI Formula

Each variable is scored based on its performance against a competitive benchmark and weighted according to its relative importance in the local news digital subscription business model, with all weights summing up to 100%. Mather presented a case study of how the Philadelphia Inquirer improved their SPI at the 2025 INMA Media Subscriptions Summit (Download the session).

Let’s explore each of these variables in more depth, highlighting the Inquirer’s success and some opportunities for publishers to improve their relative performance.

Audience Growth (AG)

• Why is it important? Top-of-funnel growth is the lifeline for publishers to continue to grow their audience and expand the reach and impact of their journalism. It is the fuel that drives the engine.
• Opportunities to improve AG include: Content strategy, content verticals, new products, partnerships, and off-platform distribution.
• Metric(s): Monthly average users year-over-year growth.

Audience Engagement (AE)

• Why is it important? While total audience reach is important, building an engaged audience is even more critical to long-term success. High levels of engagement are excellent predictors for subscriber acquisition and retention.
• Opportunities to improve AE: Personalization, habit-building items like games and puzzles, newsletters, email alerts, and push notifications.
• Metric(s): Visits per visitor, visit duration

Conversion Effectiveness (CE)

• Why is it important? To be a top performing publisher with digital subscriptions, you need to be excellent at converting your visitors into subscribers. While in absolute terms only a small percentage of users convert to subscribers, improving performance here allows publishers to scale digital subscription volumes.
• Opportunities to improve CE include: Dynamic paywalls, optimizing the checkout process, improved user experiences, and personalized subscription offers.
• Metric(s): Conversions per million users.

Churn Mitigation (CM)

• Why is it important? Once you acquire a subscriber, you have to keep them. Also, the more successful publishers are at acquiring subscribers places downstream strain on subscriber retention. And as publishers increase their maturity, churn mitigation becomes a greater focus.
• Opportunities to improve CM include: Involuntary churn, improving engagement, churn modeling, stop/save offer management.
• Metric(s): Monthly churn rate.

Average Revenue per User (AR)

• Why is it important? Average revenue per user (or subscriber) is perhaps the biggest lever local publishers have in their toolkit to scale digital subscription revenue. As sub-scale businesses, having a higher ARPU is a much more realistic path to sustainability than scaling subscriber volume.
• Opportunities to improve AR include: dynamic digital pricing, pricing tiers, product bundling, and optimized offers.
• Metric(s): Average revenue per user.

Subscriber Penetration (SP)

• Why is it important? Subscriber penetration weighs the publisher's historical activity in converting a percentage of its audience into digital subscribers. This relative metric also allows for comparisons across peers and markets.
• Opportunities to improve SP include: excelling at the other five metrics, clear strategic focus on scaling digital subscriptions and a bias for action to move quickly.
• Metric(s): Subscriber penetration (total subscribers divided by monthly average users).

Mather calculates the publisher's performance on each of these six variables into a weighted Subscription Proficiency Index. Here, you can see how the Inquirer scored a 71 (out of 100) in their recent SPI evaluation, which is up significantly from two years ago and places them in the top-performing segment.

The question we hear most often is: What is the most important metric to grow our digital subscription business?

Our answer: Your SPI score.

The SPI provides a holistic, data-driven view of your performance. It reveals where you're excelling, where you’re falling short, and how to strategically evolve your digital subscription model.