Carriers publish a dividend scale interest rate every year and agents quote it like a yield. It isn't one, and treating it as one leads people to buy the wrong policy.
The dividend scale interest rate is one input into how the carrier calculates the dividend. It gets applied to the policy's reserve, not to the premiums you've paid and not to your cash value. Then mortality experience and expense experience get factored in, and the result is the dividend that actually lands in your contract. Two carriers can publish identical rates and pay noticeably different dividends, because the other two components differ. What a dividend is actually made of is the longer version of that.
Your actual return is a separate calculation entirely. It's the internal rate of return on your cash value against the premiums you've put in, and in the early years it's negative regardless of what the dividend rate says, because acquisition costs come out first. It climbs, crosses zero somewhere in the middle years depending on design, and settles into a long-run number that is not the dividend scale rate. It's typically lower, and it's the number that matters to you.
So when you're comparing companies, ask for the illustrated net cash value at year 10, 20, and 30 on the same premium and the same design, and compare those. That comparison includes everything: the dividend rate, the mortality experience, the expenses, and the design. The published rate includes one of the four.
Two more things about the published number. Dividends aren't guaranteed, no matter how long a carrier has paid them, and a long payment history is a statement about the past. And a carrier that raises its scale in a year when its expenses also rose can pay you the same dividend as last year. The rate moved, your money didn't. Once it's declared, what you do with it is a bigger decision than which carrier published the higher number.