The home pages of several mobile travel sites were more sluggish last week compared to a week earlier according to the Mobile Speedometer, a weekly performance index ranking 19 mobile sites by speed. Travel sites are establishing a trend of falling behind other categories in load times in the recently launched Mobile Speedometer.

Expedia’s average mobile home page load time experienced some delays for the week ending June 5, slowing by 220 milliseconds compared to a week earlier, according to the data from digital performance analytics company Catchpoint Systems Inc., which provides the Mobile Speedometer performance data about how fast mobile home pages load exclusively to Mobile Strategies 360.

“A number of sites slowed slightly week over week, especially in the travel category, whose average load time increased by 70 milliseconds, coinciding with heavier pages,” a Catchpoint spokesman says.

Daily deal and local voucher site Groupon Inc.’s page load time also slowed by 200 milliseconds, mainly because its home page included slightly more items from slightly more hosts than the week before. Items are web page components, such as files or images, that a page loads from internal and external hosts or domains. These can include PDFs, PNGs, JPEGs and GIFs. Hosts are domains that deliver data, content or services over the internet to the site.

A bright spot in this week’s index is online marketplace Etsy. It showed the strongest improvement, shaving 60 milliseconds off its load time without reducing its page weight, the spokesman says. Expedia, Groupon and Etsy all did not respond to a request for comment.

The top five performers for the week are:

Find out where the other companies fell by viewing the full index here.

Travel sites again fell toward the bottom of the list, and as a category averaged a 2.58-second mobile site home page load time. The index average is 2.11 seconds. Travel sites often have difficulty loading quickly because they frequently need to wait on outside hosts to serve such as information as fare and scheduling data, Catchpoint says.

The Mobile Speedometer index monitors 19 sites across travel, retail, financial services, dining and entertainment, and healthcare. The 19 mobile sites were selected by the editors of Mobile Strategies 360.

Catchpoint Systems monitors each mobile website’s home page with measurements taken from 27 Catchpoint Systems backbone monitoring nodes across the U.S., at intervals of two minutes between Sunday to Sunday each week. Backbone monitoring nodes are the locations of Catchpoint’s devices that are near data centers of the main internet service providers that provide service to a city. The nodes simulate end-user contact with each website. Catchpoint monitors webpage load time, availability, hosts and items.

They are defined as follows:

Webpage load time: The time it takes for enough page elements to load for a consumer to begin interacting with a page, such as searching, tapping or scrolling. From a consumer point of view, the time it takes for the progress bar or spinning wheel to stop.

Availability: The percentage of time during the test week that the site can be successfully reached by a consumer.

Host: Any domain that delivers data, content or services over the internet to the site.

Items: Also known as requests. Webpage components, such as files or images, that a page loads from internal and external hosts or domains. These can include PDFs, PNGs, JPEGs and GIFs.

The companies are ranked each week based purely on their webpage load time on 4G networks.

For the week ending June 5, the average mobile site page load time was 2.11 seconds compared to 2.10 seconds the previous week. The mobile site average page weight was 1.07 megabytes compared to 1.09 the previous week. The average number of hosts was 23.43 compared to 23.00 the previous week. The average number of items on the home page was 81.40 compared to 81.00 the previous week. And the percentage of the time the mobile sites were available was 99.82% compared with 99.97% the previous week.

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