  We present microlens parallax measurements for 21 (apparently) isolated
lenses observed toward the Galactic bulge that were imaged simultaneously from
Earth and Spitzer, which was ~1 AU West of Earth in projection. We combine
these measurements with a kinematic model of the Galaxy to derive distance
estimates for each lens, with error bars that are small compared to the Sun's
Galactocentric distance. The ensemble therefore yields a well-defined
cumulative distribution of lens distances. In principle it is possible to
compare this distribution against a set of planets detected in the same
experiment in order to measure the Galactic distribution of planets. Since
these Spitzer observations yielded only one planet, this is not yet possible in
practice. However, it will become possible as larger samples are accumulated.
