Here, in its entirety, is the report as penned exclusively for this publication by Drit Suljoti, cofounder and chief product officer of Catchpoint.

As mobile sites embraced more images and third-party tags this quarter, retailers saw their average mobile page weight increase once again in the third quarter (Q3). 

The average mobile homepage now exceeds 1.45MB, a 24 percent increase from Q2. And not surprisingly, this increase correlates to an increase in render time, with an average mobile site load time of slightly less than three seconds even without factoring in external noise such as network and device bandwidth limitations. This represents a 24 percent performance decrease, directly attributed to the increased page weight. 

The average number of hosts and items on retail mobile homepages also increased by 17 percent and 19 percent, respectively.

This does not bode well for the retail industry?s mobile Web performance prospects for the upcoming holiday shopping season. 

The average site size grew quite a bit during the Thanksgiving week sales in 2014, and with three consecutive quarters of increased page size and slower load times, it would seem that mobile shoppers may be in store for longer wait times next month as they hunt for Black Friday and Cyber Monday deals.

Gap, Grainger, Amazon and Costco once again find themselves among the top five fastest mobile sites, with Gap claiming the top spot. And Newegg moves into the top five for the first time since we began benchmarking these mobile sites last year.

Top performers (mobile webpage load time):

1. Gap

2. Grainger

3. Amazon

4. Costco

5. Newegg

Travel mobile sites also saw their average page weight, load time, hosts and items count increase from Q2. The silver lining: the increases were not quite as dramatic, with the average page weight expanding only 10 percent and the load times increasing by 20 percent. 

Still, this should not be considered a huge win for an industry so focused on mobile performance. 

Mobile sites are prone to more performance issues than their desktop counterparts due to the bandwidth restrictions on mobile networks and devices. Therefore, mobile site managers must aim to keep their sites as lean as possible. 

This can be especially difficult in travel, as high-res images are a key part of showcasing the different destinations and properties on their sites. 

To be fair, the industry is proving more adept than retail, with the average mobile travel homepage coming in under 1MB and the load times well three seconds. 

However as long as travel mobile sites continue to increase page weight, it will be harder to keep load times in check.

Q3?s list of top performers is once again anchored by Google Flights (mobile webpage load time of less than one second, at 699 ms), which has claimed the top spot every quarter since this benchmark?s inception. 

TripAdvisor is one of the most notable climbers, moving up from fifth to second place thanks to a lean page ? it has the fewest hosts and items of any site tested ? and strong optimization techniques.

Top performers (mobile webpage load time):

1. Google Flights

2. TripAdvisor

3. Priceline

4. Southwest

5. Hipmunk

Making it three-for-three, banking sites also saw page weight increases across the board, though they remain the fastest and lightest across the three industries. 

The average mobile page weight of 646KB and average mobile webpage load time of 2.3 seconds represent increases of 20 percent and 12 percent, respectively.

Perhaps the most alarming statistics are the average number of hosts (rose by 33 percent) and items (rose by 44 percent) on mobile banking homepages. 

Beyond the performance risks that can result, banks have to especially careful about the number of third-party elements on their pages due to the sensitive nature of the data they display. Even if there are no actual security risks, banks can put their customers? minds at ease while increasing performance by keeping the number of hosts to an absolute minimum. 

This is the highest number of hosts and items tracked on mobile banking sites since we began monitoring them. 

In terms of the best performers, TD Bank takes the top spot by a wide margin as the only mobile banking site to render in less one second. 

Elsewhere in the top five, Capital One jumps all the way from seventh last quarter to third, thanks to a 10 percent speed improvement. 

Capital One was one of only three sites to actually improve on last quarter?s numbers.

Top performers (webpage load time):

1. TD Bank

2. US Bank

3. Well Fargo

4. Citizens Bank

5. Capital One

It is hard to look at the trends that we saw in Q3 2015 and not get concerned that things are getting too heavy. 

If page weights were increasing while the mobile site load times were staying the same or improving, it would not be such a problem. In fact, it would show that IT operations teams were getting better at optimizing. 

Without such methods in place, however, heavier pages lead to longer load times, and many organizations need to pay more attention to keeping their pages as lean as possible, especially as the holidays approach.