Is DDT a DUD?

So, off I went on the little voyage of discovery, calculating dividend doubling times for a few of my holdings.

Now, it's not simply a doubling of the dollar value of a year's dividends that interests me. You can look that up in a decent brokerage webpage or elsewhere. I'm interested in the time it takes for my actual dividend payments per year to double, taking into account the incremental increase in dividends paid as well as the effects of dividend reinvestment on the cash flow within the position year by year.  

As usual, I did this in a "quick and dirty" fashion by looking at actual dividends paid, quarter by quarter,  for companies I have held over several years. It turns out, I have made incremental investments in most of them, so I do not have a position that has been intact long enough to double purely on the basis of dividend increases and dividend reinvestment.  One can calculate a rate of dividend growth from one year to the next, however, and it's interesting to note that most of my holdings have dividend growth rates of between 7-12%.  This is achieved by dividing the dividend received in a given quarter from one year into the dividend received in the prior year. A number a bit greater than one appears, from which you subtract the number 1 and multiply the result by 100 and you have the rate of growth in percent. Using the rule of 72, you can divide 72 by the number you get and the doubling time will appear. My dividend doubling times range from 5-10 years for most stocks, less for a couple.  The dividend doubling time, averaged across the portfolio would be a great number to have, as it predicts the time at which I might possibly receive adequate dividends to replace the income I earn with my labor.

Just as the dividend growth rate varies from year to year, the dividend doubling time varies as well.
It's important to realize however, that the published rate of dividend growth under-estimates the dividend doubling time if you are a DRIPer, because your stock count is growing at the rate of the current yield in addition to dividend increases programmed by company management.

A high dividend company like T will experience a dividend doubling of 14.4 years on a static dividend. You don't have to raise the dividend by much to reduce the doubling time to under 10 years, due to the dominant effect of a dividend reinvestment of 5% every year.

Finally, you can't ignore the "new money effect" of additional contributions to the portfolio. That isn't investment performance in it's purest sense, but since I am the investor, the rate at which I save is a piece of my portfolio growth performance.  I have been adding to my retirement portfolio at the highest rate allowed by the law and will continue to do so until I stop earning a paycheck. That currently is adding about 5% per year to my nest-egg. If you treat the new money like additional dividends,  adding the current portfolio dividend yield to the new addition, gives a dividend rate of approximately 8%, which in itself produces a dividend doubling time of 9 years.
When I look at the actual dollar figures, new money plus dividends is adding 9.5% cash to the portfolio every year, and the dividend is rising by 10% per year. That results in a dividend doubling time of 7 years.

I don't think DDT is a DUD. It tells me about where I'll be in 7 years with respect to cash flow derived from my retirement portfolio.