Appending linear rises like this isn't a very useful thing to do; but I'm giving it here as another illustration that your intuitions about mathematics of trend lines are letting you both down. (judithcurry.com)
Oblique's long linear rise refuses the usual juncture - like experience of observing discrete artworks in a gallery, offering instead a syncopated ebb and flow of images. (brooklynrail.org)
Alternatively, the tide gauge at Nyborg, Denmark, and its harbor, Slipshavn, are situated in a techtonically inert zone, where ground is neither rising nor subsiding, and records a continuous 130 year unchanging linear rise of 1.1 mm / yr. (judithcurry.com)