Slides from a recent webinar offering a sneak peek of my new book, Time Is Money (to be published by O'Reilly Media in 2016). We took an historical walk -- from 2008 to the present -- through some of the many case studies that make an appearance in the book, demonstrating the impact of performance on a variety of metrics such as bounce rate, page views, traffic, revenue, and customer retention.
8. Start render DNS TCP TTFB
DOM loading DOM ready Page load Fully loaded
User timing Resource timing Requests Bytes in
Speed Index Pagespeed score 1s = $$ DOM elements
DOM size Visually complete Redirect SSL negotiation
15. Shopzilla
• Sped up average page load time from 6s to 1.2s.
• Experienced a 12% increase in revenue and a 25% increase in page views.
• Doubled the number of sessions from search engine marketing.
• Cut the number of required servers in half.
Mozilla
• Shaved 2.2s off landing page load times.
• Increased download conversions by 15.4%.
Yahoo
• Increased traffic by 9% for every 400 milliseconds of improvement.
AOL
• Visitors in the top ten percentile of site speed viewed 50% more pages
than visitors in the bottom ten percentile.
17. Average revenue loss per hour
of downtime
Average revenue loss per hour
of performance degradation
(slower than 4.4s)
$21,000
$4,100
However…
Source: TRAC Research
23. 2% increase in conversions
for every 1 second of improvement
24. Walmart also found…
Converted shoppers were served pages
that were 2X faster than pages served to
non-converted shoppers.
Non-buyers were served category pages that
were 2-3 seconds slower than category pages
served to buyers.
For every 100 milliseconds of improvement,
incremental revenue increased by up to 1%.
31. Conversion rate shrinks by about 50%
when load time for “browse” pages
increases from 1 to 6 seconds
32.
33. Do you know how performance
affects different pages
on your site?
34.
35. What is the Conversion Impact Score?
The Conversion Impact Score (CIS) is a relative score that
ranks page groups by their propensity to negatively impact
conversions due to high load times. For each page group,
the Conversion Impact Score is calculated using the
proportion of overall requests that are associated with that
group, along with the Spearman Ranked Correlation
between its load times and number of conversions. The
Conversion Impact Score will always be a number between
-1 and 1, though scores much greater than zero should be
very rare. The more negative the score, the more
detrimental to conversions that high load times for that
page group are, relative to the other page groups.
48. User expectations and behavior
are always changing
Our tools for measuring ROI are evolving
Know your own business success
metrics
Understand your own visitors
Target the best (not the slowest) pages
for optimization
Monitor, test, repeat
The people at WalmartLabs (a technology incubator under the Walmart umbrella) knew that Walmart.com was suffering from performance issues. As a for instance,
initial measurement showed that an item page took about 24 seconds to load for the slowest 5% of users. Why? The usual culprits: too many page elements, slow
third-party scripts, multiple hosts (25% of page content was served by third parties), and various best practice no-nos.
WalmartLabs dedicated a scrum team to one sprint of performance optimization. At the start of the process, the team performed some baseline measurements in which
they used their real user monitoring (RUM) data to look at the load times of key pages and look for patterns. Then the team created targets for page performance and, at the end of the sprint, measured the impact of optimization on key metrics.
Their findings showed a strong correlation between performance and conversions:
• Overall, converted shoppers were served pages that loaded twice as quickly as pages served to non-converted shoppers.
• This trend persisted, even on individual pages that experienced greater load times.
• Non-buyers were served category pages that were 2-3 seconds slower than category pages served to buyers.
• For every 1 second of improvement to load time, the site experienced up to a 2% improvement in conversion rate.
• For every 100 milliseconds of improvement, they grew incremental revenue by up to 1%.