I wonder if anyone would have any information on how many new electrical hot-water geyser systems are sold in SA, each year?

I am doing market research & have built up a rough estimate, based on a few rules-of-thumb. I would very much like to tighten the estimate, if at all possible.

What would also be incredibly useful is a further breakdown into the number of 1kW, 2kW, 3kW, & 4kW systems are sold per annum.

Links to useful information would be most gratefully received.

Thanks so much,
desA