Dalton Adding Machine serial numbers, estimated agelist

An estimated, approximate agelist for Dalton Adding Machines; serial numbers are start-at for the year.

The ~1927 issue of Business Machines and Equipment Digest contains an estimated serial numbers agelist. This list with details about changes over the years was likely provided by the Dalton company itself. 

Taking this list as a starting point, a full agelist with serial numbers from the start of production in ~1907 to the end around 1933 was estimated.

Added were any hints from period literature (e.g. start of active marketing), advertising and competition. E.g. the introduction of the Special 100-dollar Dalton was very likely the direct consequence of the Burroughs Portable being introduced in 1925 for 100 dollar.

The Dalton machine was probably also expensive to manufacture, relative to the Burroughs Portable. Even after the re-design into the Super Model range; this replaced many castings with stamped parts, but the machine was still very heavy for its capability and remained fairly complex in assembly. The Special being offered for 74 dollar via Sears in late 1929 must have been bad for margins - Dalton was likely losing badly from Burroughs by then and perhaps 'desperate measures'. 

The Brennan, despite its unfortunate launch-timing in 1929 was a 'better' machine than the Dalton. It will have been significantly cheaper to manufacture, was more compact and offered roughly the same functionality. Even though adding machine sales overall probably 'tanked' the years after the Wall Street Crash, the Brennan would have been a competitive 10-key offering versus the by-then aged (old-fashioned?) Dalton. (Notable that Remington-Rand hardly used the Dalton brand for their new Portable adding machine, but instead mostly marketed these from around '32 as Monarch or Remington-Rand.)

The published agelist in the Digest shows an overlap of Old Style and Super Model production - putting this in a graph gives a good impression of average annual volume of Dalton. It also suggests that annual sales of the Dalton company were probably around USD 20M at its peak.

The serial numbers after ~1929 become more uncertain and rough estimates. The company probably struggled as part of Remington-Rand, but would surely have continued to manufacture and sell machines right up to the switch-over to the Brennan-derived machine. Doing a quick inventory of machines that can be 'sighted'; the serial numbers probably did not go much beyond 212,000.

The sightings also give a clue to the different color-schemes of Dalton machines. From the start of production up to around 1926 the machines are lacquered plain black. In 1926, there was a switch to a crackle black and for the Special machines a 'crystalline green' finish. The Specials were finished in green for several years, but not all Specials - there are also crackle black specimens.

Then in 1928 Dalton switched to the brown woodgrain finish - judging from typewriters in woodgrain finish, that was just about then becoming very fashionable (and practical for manufacturing).

With more data and analysis, the agelist and e.g. the chronology of finishes can certainly be corrected and improved upon - this is a quick, first guess/estimate.

Anyways distilling all this; an estimated (!) agelist for Dalton Adding Machines :)