It was another roller coaster year for dance in Washington -- lots of ups, lots of downs, and no clearly discernible new patterns or trends. There's been one rather alarming tendency, already visible last year, but perhaps dismissible then as a temporary drift. Both money and viable performing spaces for dance appear to be diminishing. We've witnessed -- mainly during the '70s -- the dance explosion. Unless the future takes a dramatic turn for the better, we may be on the brink of the dance implosion.

All the same, there was no lack of high spots over the past 12 months. The year began, and is now ending, with American Ballet Theatre at the Kennedy Center. Mikhail Baryshnikov's new production of "Cinderella" ended its world premiere run last New Year's Day. And like the scullery waif of the fairy tale who surprised everyone by showing up at the prince's ball in the most resplendent gown, "Cinderella" survived a barrage of bad press (there were a number of positive reviews, including my own) on its tour, and proved itself both popular with audiences and a moneymaker. Tonight marks its final performance the second time around in Washington.

The most rewarding additions to the repertory for ABT's current visit (which ends Jan. 6 after the company premiere of Sir Kenneth MacMillan's "Romeo and Juliet") have been Balanchine's sparkling "Donizetti Variations" and David Gordon's provocatively witty "Field, Chair and Mountain," given its world premiere here Dec. 20.

The other major visiting troupe that has been in Washington twice this year was the Joffrey Ballet, which appears to have taken some giant strides in stature. Highlights of the troupe's most recent visit, just this month, included the first American production of John Cranko's "Romeo and Juliet," in performances that showed the Joffrey more than equal to the demands of full-length story ballet; a stunning interpretation of William Forsythe's daring "Love Songs"; and a very impressive program in salute to the great British choreographer Sir Frederick Ashton, now in his 80th year.

The Joffrey's earlier appearance last February fell directly between those by two other New York companies -- the Dance Theatre of Harlem, which brought a trenchant revival of Agnes de Mille's "Fall River Legend," and the New York City Ballet, featuring a glorious plethora of works by Balanchine and Jerome Robbins, as well as new pieces by Peter Martins and Helgi Tomasson.

Particularly notable among visiting contemporary groups were the Bucket Dance Theatre, Garth Fagan's excitingly youthful ensemble from Rochester, N.Y., giving eclecticism a whole new, positive look; Molissa Fenley and Dancers, who performed the superenergetic "Hemispheres" in two area sites last winter and this fall; and Bill T. Jones/Arnie Zane and Company, which brought a trendy but power-packed opus to Montgomery College's handsome new Performing Arts Center.

Among indigenous troupes, the Washington Ballet had a lively year touring overseas and elsewhere, and performed three times locally (in addition to its annual "Nutcracker" run). But it had no new work by resident choreographer Choo San Goh, who was busy preparing his first full-length ballet -- an admirable version of "Romeo and Juliet" premiered by the Boston Ballet in May -- as well as other outside commitments. Outstanding among nonballetic events in the area were the Pola Nirenska concert at Marvin, testifying to her signal contribution as a choreographer here over three decades; Liz Lerman's new installment of her sociopolitical "Docudance" at WPA; Melvin Deal's "Black Dance '84" festival, presented this year at Cramton Auditorium; and the Maryland Dance Theater's first Marvin Center appearance, with a provocative new piece by director Larry Warren.

There were some very special performances in other categories, starting with the controversial avant-garde troupe Sankai Juku, which created a sensation with its upside-down descent from the roof of the National Theatre in October, as well as with its evening-length production at the Warner; the John Curry Skating Company at Kennedy Center last summer; the Jazz Tap Ensemble, enlivening the Dance America series at the Terrace Theater in the fall; the Copasetics, showing up unexpectedly in Rockville in September; Kol Demama, Moshe Efrati's unique deaf-and-hearing troupe from Israel, which made up for its lackluster choreography with thoroughly galvanized dancing of very high quality; Geoffrey Holder, who presented his flamboyant one-man tour of dance history at the Smithsonian; Meredith Monk, who offered a solo concert of her music for voice and piano, but inevitably moved in fascinating fashion as well, at the Hirshhorn; and the extraordinary program of Middle Eastern folk dance from Jordan, Saudi Arabia and Morocco at Lisner last August.

The shrinkage in dance resources drew special notice in the fall, when the Kennedy Center reported that ABT and the New York City Ballet were among visiting attractions that had cost them six-figure losses over the past fiscal year. ABT was down to three weeks in Washington this year from its former customary seven; the New York City Ballet came for two weeks, but will not return for '85-'86. The outlook for visits by both troupes seems uncertain -- an extremely disturbing state of affairs. Hanging in the balance may be Washington's status as the second leading dance city in the nation. Coincidentally or not, this was the first year the Kennedy Center Honors failed to include a dancer or choreographer among its honorees.

In Washington, dance troupes are scrambling for both studio and performance space. The Lansburgh project is apparently crumbling -- one tenant, Liz Lerman's Dance Exchange, has already removed itself to Glen Echo; another, the African Heritage Dancers and Drummers, also will probably also be forced to relocate. The YWCA terminated its performance program at Penney Auditorium, and Glen Echo's annual summer festival has continued to diminish in scope and quality.

The positive sides of the picture include the ongoing rehabilitation of Cheverly's Publick Playhouse, reportedly with a special eye toward dance requirements, and the wonderfully equipped, splendidly designed new facility at Montgomery College in Rockville.

The biggest plus along these lines, however, continues to be the Dance Place and its still-expanding performance activities -- this year a summer series was added to the one that now extends weekly from fall to spring. A recent major development has been the inclusion of the Dance Place in the newly announced National Performance Network, which will add substantially to its ability to sponsor venturesome troupes from other parts of the country.

Among other encouraging occurrences were several events taking innovative approaches to the presentation of Washington dancers and dance troupes. Among these were Murray Spalding's "Dance Spotlight," which offered local, national and international attractions on a single program; George Washington University's "Dance Directions '84," which presented a generous sampling of Washington companies in three programs; and "The Smithsonian Salutes Washington Dance," a four-segment festival that will have a new edition in 1985.