To form a right judgment of it, indeed, we must compare the state of the country at periods somewhat distant from one another. The progress is frequently so gradual that, at near periods, the improvement is not only not sensible, but from the declension either of certain branches of industry, or of certain districts of the country, things which sometimes happen though the country in general be in great prosperity, there frequently arises a suspicion that the riches and industry of the whole are decaying.
– Adam Smith (1776) 
Using my newly acquired Fall/Winter 1956 Sears catalog  I searched for the lowest-priced women’s casual clothing ensemble available in 1956 that I could find, subject only to the constraint that that ensemble be something reasonably close to what an American woman in 2012 might wear. So I selected an ensemble that consists of (1) a pair of jeans; (2) a cotton (or cotton-blend) blouse; (3) a pair of heeled pumps; (4) a pair of nylon panties; a (5) a bra.
In 1956, a woman shopping at sears and searching for the lowest-priced of each of the above five items would have paid the following 1956 prices:
(1) jeans: $2.29
(2) blouse: $1.25
(3) pumps: $3.98
(4) panties: $1.29
(5) bra: $0.95
In total, that young woman of my mother’s generation would, in 1956, have paid, pre-sales-tax, $9.76 for this low-priced, simple ensemble. If that woman earned the then-average hourly manufacturing earnings of production workers, as reported in Table 1 here , she would have earned, pre-income and payroll taxes, an hourly sum of $1.89. Therefore, this woman in 1956 would have had to work 5.2 hours to earn enough money to buy this low-priced clothing ensemble.
How did this young woman from the mid-1950s fare on this front compared to a young woman in today? Alas, pretty poorly. Searching on Sears’s website I found the lowest-priced jeans, blouse, pumps, nylon panties, and bra sold today. Here are the prices (as listed on that website on 16 December 2012):
(1) jeans: $17.99 
(2) blouse: $8.99 
(3) pumps: $16.99 
(4) panties: $4.20 
(5) bra: $9.00 
A woman today, therefore, would spend a total, pre-sales tax, of $57.17 to buy this low-cost clothing ensemble at Sears. (I suspect that she could find even lower prices at Wal-Mart, but I didn’t check there. It’s the holiday season and one must husband wisely one’s shopping time.) If today’s woman earns the closest earnings figure that I can find to the one for which I have data in 1956 – namely, the average hourly earnings of nonsupervisory nonfarm private production workers in the U.S. , that figure being $19.84 (as of November 2012) – she would have to work only 2.9 hours to buy this low-priced clothing ensemble. That is, an inexpensive, yet new and decent, casual clothing ensemble for a woman cost only 56 percent of the work-time of an ordinary full-time American worker today that such an ensemble cost a similar worker in 1956.
Examined product by product, each of these clothing items costs less work time today than it cost in work time in 1956.
(1) jeans: in 1956 they cost 121 percent of the typical worker’s hourly wage; in 2012 they cost only 91 percent of the typical worker’s hourly wage
(2) blouse: in 1956 one cost 66 percent of such a worker’s hourly wage; in 2012 one costs 45 percent of that wage
(3) pumps: in 1956 a pair cost 211 percent of such a worker’s hourly wage; in 2012 a pair costs 86 percent of that wage
(4) panties: in 1956 a pair cost 68 percent of such a worker’s hourly wage; in 2012 a pair costs 21 percent of that wage
(5) bra: in 1956 one cost 50 percent of such a worker’s hourly wage; in 2012 one costs 45 percent of that wage
Many more posts such as this one are on their way.
UPDATED WITH CORRECTION: After browsing my 1956 catalog more carefully, I found a less-expensive pair of women’s pumps than the pair that I reported in the first version of this post. The resulting price of these pumps fell from $5.98 to $3.98.