Tammy Everts stands for the topic “page speed load” and is usually referenced to with other names like e.g. Steve Souders and Stefanov Stoyan. Just recently she released a presentation on “The Real Cost of Slow Time vs. Downtime“.
In general, the calculation for downtime losses is quite simple:
downtime losses = (minutes of downtime) x (average revenue per minute)
Calculating the cost for slow page performance is ways more tricky since the impact is deferred to the actual accurance of slow pages. The talk basically differentiates between short-term losses and long-term losses due to slow pages.
- Identify your cut-off performance threshold (4.4 seconds is a good industry value)
- Measure Time to Interact (TTI) for pages in flows for typical use cases on your site
- Calculate the difference of TTI and cut-off performance threshold
- Pick a business metric according to industry best practice. 1 second delay in page load time correlates to
- 2.1% decrease in cart size
- 3.5-7% decrease in conversion
- 9-11% decrease in page views
- 8% decrease in bounce rate
- 16% decrease in customer satisfaction
- Calculate losses
The long-term impact is calculated on a customer lifetime value (CLV) calculation basis. The relationship – according to studies – between CLV and performance is interesting. 9% of users will permanently abandon a site that is down temporarily – but 28% of users will never again visit a site showing inacceptable performance.
- Identify your site’s performance impact line (8 seconds is a good industry value). Above this timeline business really got impacted.
- Identify the percentage of traffic experiencing slower traffic than the impact line.
- Identify CLV for those customers
- Calculate loss knwoing that 28% of these customers will never return to your site.
The presentation “Getting page speed into the heads of your organization – a first hand report” (
) talks about the impact of web page speed and how to get the importance into the heads of your organization.
It also talks about the measured business impact of web page speed onto our online dating business. Those insights might be handy if you’re looking for recent information published in the context of web site performance impact on business. Our BI-team did an analysis of the impact of our performance improvements reported in the referenced presentation. Here’s our key learning.
What did we achieve?
- We reduced the page load time by 27% from 2.96s to 2.15s
- We reduced the app server response time by 25% from 365ms to 275ms.
What is the impact?
- We reduced the number of profile resigns by 24%
- We increased the number of messages by 71%
What does this mean?
In online dating, revenue is a function of activities. The more active people gather on an online dating site, the more revenue is typically seen in the business. Activity on the other hand is a complex function of ‘messages transported’, ‘searches done’, ‘profiles viewed’, ‘pictures seen’ and so on.
So, in our case. The decrease in page load time led directly to higher activity on our platform. Higher activity leads to higher revenues. We’ve seen our impact on revenues driven by reduced page load time.
Just recently in Hamburg, I had the pleasure of talking to web site performance addicted people – on the 17th Web Performance Meetup. I talked about the way we at FriendScout24 got the importance of web page speed into the heads of our organization. The whole presentation is available publicly.
Page load time is critical. A lot of people highlight the importance of fast web sites. Amongst them are Steve Souders, Patrick Meenan, Tammy Everts, Stoyan Stefanov and others.
What to do to make your site run fast? There are tons of pages, blogs, hints, tips, tricks and other stuff around in the web. Here’s my favorite collection:
At FriendScout24, we follow this idea of fast web pages as well. I talk in another post in greater details about our goals, achievements and how we actually did it.