Turnstile nation

WHAT was it that young Dorothy said in ``The Wizard of Oz,'' commenting on the sudden departure of one of the mysterious folk who peopled her unusual tale? ``My goodness,'' she exclaimed, perplexed. ``People come and go so quickly around here.'' We're reminded of Dorothy's observation, here paraphrased, because it says as much about Dorothy's turn-of-the-century United States as it does about the imaginary land of Oz.

As new evidence just released by the nonprofit Population Reference Bureau suggests, people in the United States have been coming and going over the years. That is, they have been actually leaving the country far more than was previously recognized.

The ratio, of course, has been weighted more on the side of immigration (coming) than emigration (going): a roughly 3-to-l ratio in favor of immigration. The immigration numbers (some 30 million newcomers since 1900) are not surprising, given the need to build a substantial population base. But what is interesting about the new study, ``The Elusive Exodus: Emigration From the United States,'' is that millions of persons living in the US -- as many as 10 million -- have taken the reverse journey since 1900, leaving the US. Reasons vary: Some folks decided to return to the familiarity of the ``old country.'' Others have gone for political or cultural reasons.

The numbers say much about the United States: its openness as a society, compared with many parts of the world, where to leave a border is to bring out rifle-toting guards. The numbers also remind Americans of their sense of adventure -- the grit that settled the Old West.

Quietness, steadiness, continuity -- these are valuable qualities. But coming and going can also have its place. The new emigration statistics emphasize that America's membership roll has not remained fixed. And they remind Americans once again that continued legal immigration has its uses, at least partly to help counterbalance those who, for whatever reasons, find ``going'' more compelling than ``staying.'' ------30{et