49ers offensive drive info by quarterback

Some San Francisco 49ers fans are concerned a quarterback change could be throwing off the team's formula for winning.

They realize Colin Kaepernick might offer more than Alex Smith offered, but they fear improved big-play ability could be coming at the expense of consistency. They wonder if an adjustment period could compromise a playoff push.

2012 49ers Offense by QB

A tough loss at Seattle in Week 16 amplified these fears. The 49ers seemed to get away from their strengths when they came out throwing.

Meanwhile, two of the team's best players, Vernon Davis and Frank Gore, have said they're still finding their way with a new quarterback.

Davis and Smith had worked well together for years. Gore's approach to running changes from the Pistol formation the team often uses with Kaepernick behind center.

With an assist from Hank Gargiulo of ESPN Stats & Information, I've put together a chart showing drive information for when each quarterback was in the game. Thanks to @AaronFarber for asking to see this info. Aaron wanted to see information for time of possession. I'm holding off on that because there were games when both quarterbacks played.

The 49ers' efficiency in the red zone and in overlapping goal-to-go situations has fallen off with Kaepernick. For example, the 49ers were above 50 percent in red zone touchdown percentage four times in their first eight games, all with Smith starting. They have not been above 50 percent with Kaepernick starting.

There aren't enough stats built up over time to make the numbers definitive. There are some key variables to consider.

Kaepernick has made four of his six starts on the road, some against top teams such as New England and Seattle. Removing the Buffalo game from Smith's ledger would push Kaepernick into the lead in points per drive, percentage of drives leading to touchdowns and expected points added per drive.

Those are things to keep in mind when deciding how far to run with the numbers. Also, there were drives when both quarterbacks participated. I'll look for ways to refine the information as we continue to analyze the quarterback situation in San Francisco.