Radio station WMDO, 1540 on the AM dial, was described incorrectly in a table in the March 27 issue of The Washington Post Magazine. WMDO broadcasts Spanish-language news and community affairs and Hispanic music.

The numbers game, so well understood in Washington, is fiercely played out in local radio ratings, which over the last decade have become an obsession for salesmen and advertisers exchanging time for money. The numbers on radio can tell you a lot about who listens to what in this town and why.

The numbers are provided by Arbitron, the audience projection conglomerate that identifies radio listeners by age, sex, socioeconomic profile, buying patterns and time-of-day listening habits.

The numbers determine what you hear between the music or the talk on radio. An advertiser who wants to sell furs might end up putting his message on WGMS, WHUR and WRMR. Expensive condominiums wind up on WGMS, WGAY, WTOP and WMAL, the less expensive ones on WPGC and WLTT. Beer sells on WRQX, WKKX and WAVA. For camping gear listen to WMZQ and WLTT. Health club memberships are sold on WASH, WMAL, and WLTT. Luxury sports cars are heard revving on WGMS, WLTT and WRQX, station wagons on WASH, WPGG, WMAL and WGAY. For Cadillacs, Mercedes and Lincolns, try WKYS, WRC and WGMS.

Harden and Weaver, on WMAL every morning, sell their time for the highest rate in town, a stupendous $525 per minute, and they're always sold out. They used to own morning radio with a 25 percent share of the listening audience, and still hold the fort with a hefty 14.7 percent (WKYS is second at that key time with an 8.9 percent share).

Such numbers can mean success or failure. Ratings are the negotiating point for advertising rates. Enough bad numbers, and station management is likely to try a turnaround with a format change. WJMD recently changed to WLTT (station announcers call it "W-lite") and from what is called beautiful music to what is called adult contemporary. Good numbers may mean your favorite talent will be heard elsewhere on the dial. WPGC, which just four years ago had nearly number-one numbers, lost Jim Elliott and Scott Woodside to WRQX's bigger bucks. WPGC now holds 14th place; WRQX is fifth.

Good numbers don't always mean a station will be besieged by advertisers for time slots. Advertisers have a lot to pick and choose from in Washington. "When you go into the Arbitron book, you look first at which stations are dominant against your demographic," says Pat Nolan of Earle Palmer Brown advertising agency. "For instance, a country station [WKIX] is targeted for adults 25 to 54; adult contemporary [WLTT, WASH] stations will hit that category very well, same for a classical format [WGMS], MOR [middle-of-the road] and beautiful music [WGAY]."

Even if the numbers for a station aren't high, the ad rates can be. WGMS with only a 2.5 audience share, has very high demand, one advertising agency representative says. "They are priced at almost the same as the top stations because demand is so great for that station that people are willing to spend over $100 per spot. The elitist, classical format is historically upscale and here there's a great allegiance because there's no threat of audience erosion."

The numbers on Washington radio and its listener habits can be mind-boggling, but here are a few to add some perspective on who's listening to what:

Washington is the ninth largest market in the country with a potential audience of 2,610,200 and an effective buying income of $45 billion. Of these residents, 1,094,100 are men over 18, 1,214,100 are women over 18 and 302,00 are teens 12 to 17.

In an average hour, 1,936,800 of Washington's potential radio audience listen to the radio for at least 20 minutes. About 98 percent of all are homes have at least one radio.

Arbitron's metropolitan survey that determines many of the numbers on Washington radio takes in the District and Montgomery, Fairfax, Loudoun, Prince William, Prince George's, Arlington and Charles counties. It reports on FCC licensed commercial stations, thus excluding public, college and high school radio. In the Fall 1982 Arbitron report, called a book, 29 local stations, accounting for 90.1 percent of the audience, were listed. Twenty stations bought the fall book, with "subscriptions" ranging from $35,000 a year paid by WEZR to $152,000 paid by WMAL-WRQX.

The most frequently bought demographic here is adults 25 to 54. The most frequently bought times are morning drive, 5:30-10 a.m.; midday, 10 a.m.-3 p.m.; and afternoon drive, 3 to 8 p.m.

WHAT WAS THAT AGAIN?

A look at how some area stations have changed their tunes. (TABLE) YEAR(COLUMN)WEAM(COLUMN)WKYS(COLUMN)WWDC(COLUMN)WXTR(COLUMN)WMD0 (COLUMN)1390 AM(COLUMN)93.9FM(COLUMN)1250 AM(COLUMN)104 FM(COLUMN)1540 AM 72(COLUMN)R&R(COLUMN)Jazz(COLUMN)MOR *(COLUMN)AdCon **(COLUMN)Country 73(COLUMN)(COLUMN)Beautiful 74(COLUMN)R&B(COLUMN)R&B(COLUMN)Music(COLUMN)Country 75(COLUMN)Rock(COLUMN)Disco 76(COLUMN)Pr.Rock 77(COLUMN)Urban(COLUMN)(COLUMN)Album 78(COLUMN)Contemp.(COLUMN)(COLUMN)Rock 79(COLUMN)Top 40(COLUMN)Urban(COLUMN)AdCon 80(COLUMN)Big Band(COLUMN)Contemp.(COLUMN)Alb. Rock(COLUMN)(COLUMN)Disco 81(COLUMN)(COLUMN)(COLUMN)AdCon(COLUMN)Oldies(COLUMN)Hispanic (COLUMN)(COLUMN)(COLUMN)(COLUMN)(COLUMN)music/news 83(COLUMN)(COLUMN)(COLUMN)(COLUMN)(COLUMN)Nostalgia(END TABLE) (FOOTNOTE)

* MOR: Middle of the Road

** AdCon: Adult Contempory (END FOOT)

-- Jane Freundel Levey

SOURCES: National Association of Broadcasters; WEAM, WKYS, WWDC, WXTR and WMDO.

HOW THEY RATE IN RADIOLAND

Arbitron average ratings for the area's top 28 stations.

Light figures are percentages, bold figures are standings. (TABLE) STATION(COLUMN)Fall(COLUMN)Summer(COLUMN)Spring(COLUMN)Winter(COLUMN)Fall (COLUMN)82(COLUMN)82(COLUMN)82(COLUMN)82(COLUMN)81 WKYS(COLUMN)9.3(1)(COLUMN)10.2(1)(COLUMN)8.4(1)(COLUMN)9.5(2)(COLUMN)8.1(2) WMAL(COLUMN)8.9(2)(COLUMN)7.9(2)(COLUMN)7.5(3)(COLUMN)9.7(1)(COLUMN)10.6(1) WHUR(COLUMN)7.5(3)(COLUMN)7.4(3)(COLUMN)6.9(4)(COLUMN)7.6(4)(COLUMN)6.2(4) WGAYfm(COLUMN)7.3(4)(COLUMN)7.1(4)(COLUMN)7.7(2)(COLUMN)7.9(3)(COLUMN)7.8(3) WRQX(COLUMN)5.1(5)(COLUMN)5.1(5)(COLUMN)4.9(5)(COLUMN)4.2(7)(COLUMN)3.8(10) WPKX(COLUMN)5.0(6)(COLUMN)3.4(13)(COLUMN)2.9(14)(COLUMN)2.9(14)(COLUMN)3.2(16) WLTT4.4(7)(COLUMN)4.4(7)(COLUMN)4.4(8)(COLUMN)3.3(11)(COLUMN)4.4(8) WAVA(COLUMN)4.0(8)(COLUMN)3.9(9)(COLUMN)4.1(11)(COLUMN)2.8(16)(COLUMN)3.3(14) WASH(COLUMN)3.8(9)(COLUMN)3.8(11)(COLUMN)3.5(13)(COLUMN)4.5(6)(COLUMN)4.6(7) WMZQ(COLUMN)3.6(10)(COLUMN)3.5(12)(COLUMN)2.7(15)(COLUMN)3.0(13)(COLUMN)3.3(14) WOOK(COLUMN)3.6(10)(COLUMN)3.9(9)(COLUMN)4.2(10)(COLUMN)3.9(9)(COLUMN)3.5(11) WRC(COLUMN)3.6(10)(COLUMN)3.0(15)(COLUMN)4.3(9)(COLUMN)2.9(14)(COLUMN)3.4(13) WTOP(COLUMN)3.3(13)(COLUMN)4.2(8)(COLUMN)3.6(12)(COLUMN)3.8(10)(COLUMN)4.0(9) WPGCfm(COLUMN)3.3(13)(COLUMN)4.8(6)(COLUMN)4.9(5)(COLUMN)4.2(7)(COLUMN)4.7(6) WWDC(COLUMN)2.9(15)(COLUMN)3.1(14)(COLUMN)4.5(7)(COLUMN)4.7(50)(COLUMN)5.1(5) WGMSfm(COLUMN)3.3(13)(COLUMN)4.8(6)(COLUMN)4.9(5)(COLUMN)4.2(7)(COLUMN)4.7(6) WWDC(COLUMN)2.9(15)(COLUMN)3.1(14)(COLUMN)4.5(7)(COLUMN)4.7(5)(COLUMN)5.1(5) WGMSfm(COLUMN)2.5(16)(COLUMN)2.5(16)(COLUMN)2.3(16)(COLUMN)3.2(12)(COLUMN)3.4(12) WYCB(COLUMN)1.9(17)(COLUMN)1.4(19)(COLUMN)2.1(18)(COLUMN)1.9(17)(COLUMN)1.0(21) WEZR(COLUMN)1.5(18)(COLUMN)1.7(18)(COLUMN)1.9(19)(COLUMN)1.8(18)(COLUMN)3.2(16) WRMR(COLUMN)1.3(19)(COLUMN).9(22)(COLUMN)1.1(21)(COLUMN)1.1(21)(COLUMN).6(23) WHFS(COLUMN)1.2(20)(COLUMN)1.4(19)(COLUMN)1.3(20)(COLUMN)1.2(19)(COLUMN)1.4(18) WXTRfm(COLUMN)1.2(20)(COLUMN)2.0(17)(COLUMN)2.2(17)(COLUMN).5(28)(COLUMN).3(28) WGMS(COLUMN).9(22)(COLUMN).6(25)(COLUMN).6(24)(COLUMN).7(24)(COLUMN).8(22) WOL(COLUMN).8(23)(COLUMN).7(24)(COLUMN).7(23)(COLUMN)1.2(19)(COLUMN)1.4(18) WEAM(COLUMN).7(24)(COLUMN).8(23)(COLUMN).6(24)(COLUMN).8(23)(COLUMN)1.3(20) WGAY(COLUMN).7(24)(COLUMN).8(23)(COLUMN).4(27)(COLUMN).6(27)(COLUMN).6(23) WUST(COLUMN).6(26)(COLUMN)1.0(21)(COLUMN).9(22)(COLUMN)1.0(22)(COLUMN).6(23) WPGC(COLUMN).3(27)(COLUMN).5(26)(COLUMN).4(27)(COLUMN).7(24)(COLUMN).5(27) WWDC(COLUMN).3(27)(COLUMN).2(27)(COLUMN).6(24)(COLUMN).7(24)(COLUMN).6(23)(END TABLE) Commercial stations not listed: WLMD, WEEL, WAGE. Noncommercial stations not listed: WETA, WDCU WPFW, WAMU, WGTS