Annual U.S. shipments of polished wire glass, after being stable during 1964-67, rose by about 20 percent in 1968. Shipments in 1968 totaled 24 million pounds, compared with average annual shipments of 20 million pounds in 1964-67. Shipments in the first half of 1969 were virtually the same volume as those in the corresponding period of 1968. Nearly all of the polished wire glass sold to others by the U.S. manufacturers is distributed through independent distributors. Yearend inventories of polished wire glass declined irregularly during the period 1964-68; they were equivalent to 17 percent of shipments in 1968, compared with 32 percent in 1964.

U.S. Imports

Annual U.S. imports of plate and float glass increased steadily during the 5-year period 1964-68 (table 17). Imports of such glass in 1968 (178 million pounds) were nearly double those in 1964 (94 million pounds). In January-June 1969, U.S. imports of plate and float glass were about 10 percent smaller than in the corresponding period

unknown degree by a lengthy dock strike at Atlantic and Gulf Coast
In 1967 and 1968 imports of plate and float
ports early in the year.
glass were equivalent to about 8 percent of U.S. consumption of such
glass, compared with about 6 percent in 1964; the corresponding ratio
in the first half of 1969 was 7 percent.

The bulk of the U.S. imports of plate and float glass consists
About three-fourths of recent

of glass that is 1/4 inch in thickness.

annual imports have been clear glass, and one-fourth colored.

All of the U.S. imports of plate and float glass in 1964-68 In the first half of 1969, entered the United States at MFN rates.

a trivial volume of such glass, equal to about one-tenth of 1 percent of total imports, was entered at full rates of duty from East Germany. Japan and Belgium were the chief foreign sources of plate and float glass in 1968; substantial quantities also were imported from Italy, Canada, France, and West Germany (table 20).

Annual U.S. imports of polished wire glass were stable in 1964-66 and then rose moderately in 1967 and 1968. Imports in 1968 amounted to 10 million pounds, a quantity some 50 percent greater than that In 1968 imports supplied 29 imported on the average in 1964-66.

percent of apparent U.S. consumption, compared with about 25 percent in 1964-66. U.S. imports of polished wire glass in 1968 came chiefly from Japan and the United Kingdom.

U.S. Exports

Annual U.S. exports of plate and float glass ranged from about 60 million to 100 million pounds in the period 1964-68. They were generally equivalent to 3 percent to 5 percent of U.S. shipments in those years; they were equivalent in quantity to 70 percent or more of annual imports of plate and float glass in 1964-66, but to 35 percent in 1968. Canada was by far the major market in the period 1964-68.

Employment in U.S. Establishments
Producing Plate and Float Glass

During the period 1964-68, about 7,000 to 8,000 workers were employed in the United States in the manufacture of plate and float glass. The annual number of man-hours worked by production and related workers in the manufacture of these two types of flat glass increased from 14.9 million man-hours in 1964 to 16.7 million in 1966, but then declined to 13.9 million in 1968. With the wide substitution of float glass for plate glass during those years, the annual manhours worked in the production of plate glass declined, while those worked in the output of float glass increased (table 21).

Plate glass

The number of man-hours worked annually by production and related

from 14.0 million in 1964 to 10.3 million in 1968. The decline was
shared by three of the four producing companies; it was generally
counterbalanced in each of the three companies, however, by increased
employment in the manufacture of float glass--although sometimes at
a different plant.

In the period 1964-68, the annual U.S. production of plate glass, the number of man-hours worked in the manufacture of such glass, and the average annual output per man-hour were as follows:

The output of plate glass per man-hour varied widely among the various producing companies, e.g., ranging from a low of 67 pounds to a high of 204 pounds in 1968. The highest output per man-hour was attained by a company making a single thickness, a circumstance

amenable to high-level output.

Float glass

As the U.S. output of float glass expanded markedly in the 5-year period 1964-68, the annual number of man-hours worked in the manufacture of such glass more than quadrupled, increasing from 0.8 million in 1964 to 3.6 million in 1968. The increased annual output of float glass was

also accompanied by a steadily growing average annual output per manhour. In the period 1964-68, the annual U.S. production of float glass, the number of man-hours worked in the manufacture of such glass, and

the average annual output per man-hour were as follows:

As in the case of plate glass, the annual output of float glass

per man-hour has varied widely from one company to another. In 1968, for example, company output per man-hour ranged from 139 pounds to 568 pounds (table 23). A large part of the difference reflects the effect of new production lines coming on stream.

Polished wire glass

Annual employment in the production of polished wire glass, as well as average annual output per man-hour, was generally stable during 1964-68. About 400,000 man-hours were expended annually on the manufacture of polished wire glass. The annual output per man-hour-which was heavily weighted by the experience of the dominant producer-stood at about 71 pounds. The output per man-hour recorded by both