The short focal length lenses used for landscape photography distribute the DOF closer to 1/3 in front and 2/3 behind.
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It's a little more complicated than that. The 1/3 -- 2/3 rule of thumb has been around a long time and is commonly repeated. It has no substance in reality. Take for example a 35mm lens (wide) on a 35mm camera. Focused at 12 feet in front of the camera and set to f/8 the DOF distribution would be 12% front and 88% back. Stop the lens down further or focus farther into the scene and that distribution becomes more uneven. One more stop to f/11 and the DOF in back reaches infinity with 6 feet of DOF up front. The ratio of 6 feet to infinity sure isn't 33/66.
The DOF ratio will range seamlessly from basically 50/50 (focus close and large f/stop) to 1/99 back until back reaches infinity (focus far and small f/stop). 33/66 will occur along that seamless line. If there's a common type of photograph where 33/66 is more likely it's going to be a portrait with a portrait length lens.
Take Care,
Joe