If the expectations of Christmas presents from Washington area children are any guide, not only has the retail business just completed a banner year, but the economy should benefit in coming months from enthusiastic consumer spending.

In an interview last week, Santa Claus said he never has seen anything like the outpouring of requests for gifts he received this season. Particularly unusual, Claus added, have been the numerous suggestion for adult-type and big-ticket items.

Many of the area's children, with ages ranging up to 8 or 9 years old, asked for typewriters. Some requested new suits of furniture for their room. Tape recorders, television sets and 10-speed bicycles were common to many request lists.

Claus was interviewed by telephone from his headquarters at the North Pole, which is somewhere in Canada or the U.S.A., and with a postal ZIP code of 50902, 10001, 20013 or "unknown," depending on which letters to Santa you see.

One Silver Spring child addressed a letter to Claus at the "Toy request center, North Pole." A Washington youngster addressed requests simply, "To Santa." And another provided a street address of 144 North Pole Drive, in North Pole, N.P.

Claus made available to The Washington Post a batch of letters from children in the metropolitan area, which he said were not totally representative of youngsters across the land, because of an evident affluence in taste.

"If everyone lived in the suburbs of Washington, D.C., the nation would be enjoying an economic boom - its greatest in history," said Claus, quoting a recent Sindlinger & Co. report, which was followup to earlier Sindlinger research on the Washington marketplace.

The income levels of the counties in suburban Washington are the highest of any of 487 counties which made up Sindlinger's regular surveys of consumer attitudes.

But Claus told The Post that despite the affluence, letters from area children filled a mixed bag, literally. Both love of toys and fads and some genuine human spirit were evident.

It was hopeful to see, for example, that Washington area youngsters differed little from their counterparts in other parts of the country in terms of toy-sized heroes. Not one Washington area child's letter mentioned anything remotely related to politics, for example. Instead, there were requests for dolls of the Osmonds, Evil Knievel or Sesame Street characters. Ewen Batman and Robin were mentioned.

A good percentage of the letters offered vows of good behaviour, a characteristic that Wall Street Journal editorial writers wouldn't attach to many of the writers' bureaucratic parents.

"I have been a good boy this year and I listen to my Mommy and Daddy and I help my Mommy with my brothers," said one youngster. "I promise to try and be as good as I can," noted another.

But the most common denominator of the Washington area letters, which matched a nationwide sampling done by the Claus organization, was the direct approach employed. "Those children really are up front in telling you just what is on their minds," Claus said.

He cited the openings of some letters from Washington youths: "Please bring me the following things for Christmas," "I am writing you because I wanted you to know what I wanted for Christmas. Here is my list," and "Dear Santa, please bring."

When asked which letter from a Washington youth he enjoyed the most, Claus dug through his files for a few minutes and recovered a Dec. 1 combination of crayon drawings and eight pages of printed manuscript from a boy named Christopher.

The letter never got around to asking for presents. It began with a tribute to Claus and all of his elves. It gave names of the writer and a brother, "in case you do not know who I am," and raised an interesting question: "Is it hard flying around the world?" The youngster described how he had been studying foreign countries in school and how relatives from Germany recently came to visit. It ended with praise for the reindeer and Mrs. Claus but there was a note of skepticism, too. "Do you really have Rudolph?" he asked.

The only miracle, said Claus, is that children somehow have minds that nurture both hope about their future and doubts about the way things are said to be. He started to say something about their parents but was called away for a final briefing by intelligence aides about the current state of international borders and where he had to be careful in making deliveries.

But before he ended the interview, Claus answered one more question. Asked why he was able to keep up a heavy work pace at such an old age, he pointed to promises from many area youngsters to prepare a snack of cookies. "I have no intentions of resigning," said Claus, paraphrasing a sometimes resident of Washington who hails from the snow belt in Minnesota, named Hubert Horatio Humphrey.

"I'd have to do a count, but I suspect we're down in units," said shoeman Rich. He said inventories generally are not overloaded but like many apparel merchants, he began taking some markdowns early in December.

Vandemark said Garfinckel's inventories are "in good shape." Atlas described Herman's stocks as "very clean."

Both excutivies said they had not tried to "hype" sales with heavier than usual pre-Christmas advertising or markdowns. But many stores did their best to cash in on the last minute buying binge, as Montgomery Ward did by staying open until midnight Friday night.

There will still have to be year-end clearances, however, and many stores aren't waiting until January for white sales. After the biggest Saturday of the year, Monday "should be a big day," predicts Hecht's Bloostein, "almost everything will be on sale."

The latest Commerce Department figures available for the overall Washington area show total retail sales of $878 million for the month of September, down 3 percent from a strong August volume, but up more than 11 per cent from the $788 million estimate for the same month in 1976.

Starting with monthly data for September, the Commerce Department has revised its regular survey of retail trade across the nation. The new reports will include separate data on statewide retail sales in Virginia and Maryland as well as sales figures for geographic regions.

Commerce estimated Maryland retail sales in September at $1.2 billion off 1 per cent from August, and in Virginia gave a $1.3 billion estimate, down 3 per cent from August. No separate figure for the District of Columbia was listed.