The climatic environmental conditions a camera is routinely used in influences shutter life.
Used in climate conditions that are cool and dry helps a shutter last longer.
High humidity and temperature extremes can negatively affect shutter life.
The use of reusable silica desiccant packs in your gear bag(s) is highly recommended regardless.
The linked to chart has less than 40 data points making it a small enough sample to wonder how useful it is, notwithstanding the fact that there is no information regarding how well any of these cameras were cared for, nor the climate conditions that could have effected the shutter.