Pulsar rotation is highly periodic, but because they are every dense, pulsars have very unusual properties as well much like the property of spin of the atomic nucleus. In contrast to the nuclear spin, pulsars radiate energy from their poles and it is the precession of those energy beacons that shines much like the rotating lighthouse of maritime lore. Each time a pulsar pole happens to point to earth, we measure a pulse of that pulsar and these pulses vary from periods of several seconds to several thousandths of a second, milliseconds.
The pulsars not only tick at very regular rates, pulsars also decay at very regular rates. Some pulsars actually increase in tick rate, but the vast majority of pulsar rates decay over time. This decay rate conforms to the classical αdot = 0.255 ppb/yr decay of matter time as shown by the red dash line in the figures below. This classical decay is proportional to the ratio of gravity and the square of charge and so is the unification of gravity and charge in matter time.
Millisecond pulsars are especially accurate timepieces and their trend in the plots below show an average decay that is very similar to the classical decay, and while this could be just a coincidence, it it perfectly consistent with a shrinking universe. Also maybe coincidentally, the measured earth spin down, earth moon orbit decay, and Milky way/Andromeda separation rates happen to fall on this same line...
The larger plot below shows where the hydrogen atom and electron spin frequencies lie on the spin down line...oh, and the earth-moon orbital decay is also well known. Note that orbital decay means frequency decay and that means the orbit increases in distance in order for the period to decrease. The classical electron spin velocity, c/α, defines a period for the electron spin and the matter decay, mdot, defines the slope of the decay line. These are the two axioms that drive all gravity and charge forces.
As you can see, both c/α and mdot are simply restatements of constants of science and not new parameters. The only new parameter here is that third axiom, m¥, the mass of the smallest particle, the gaechron. The ratio m¥ / me scales gravity to charge force, but does not show up on this plot since that is the period of the universe matter pulse, 27 Byr, of which we are 3.4 Byr into that matter pulse. However, the Andromeda-Milky Way galaxies separation decays at 0.267 ppb/yr, very close to the universe decay rate.
Now added is the Allan deviation noise curves for the 171Yb/87Sr lattice clock ratio. Once the ratio noise is coincident with the universal decay constant, that is to what the clock ratio converges.