It seems bad enough that a German going to dinner in Bonn has to pay 22.5 German marks today for a steak dinner that in 1972 cost 18.5 marks.

But an American traveling to West Germany, who in 1972 paid $5.78 for the same meal, today must pay $12.50 for the same dinner -- and that doesn't include a drink or dessert.

The difference between the 22 percent increase in the cost to the German and the 116 percent increase that hit the American sitting down for the same steak dinner can be explained in five short words: The decline of the dollar.

For Americans traveling or living all over the world, the story is virtually the same. The cost-of-living increases -- traced back for the most part to the decreasing value of the dollar against foreign currencies -- have put a tighter and tighter squeeze on those living by the dollar.

The four charts accompanying this article tell the tale of the cash register tape in the clearest possible way: the bottom line.

That cup of coffee at Fouquet's on the Champs Elysees in Paris, for example -- including the obligatory service charge -- has gone from 80 cents in 1972 to $1.53 today, not to mention the almost obligatory Croissant that the proper coffee drinker also would order.

All right, we'll mention it. In 1972, the Croissant cost 11 cents, a pittance compared to the 28 cents it goes for today.

If the average traveler has any money left after visiting Paris, London can take care of that. Besides the beating the American takes for the decline in the dollar, the English have added their own problems with the value of the pound and a rampant inflation. A double room with bath at the Cumberland Hotel cost $40.94 just two years ago. Today, that room costs $68.95 -- an increase of 68 percent. Not that the British are doing much better. The same room which cost 23 pounds sterling in 1976, today goes for 35 pounds sterling -- a jump of 52 percent.

With things going so badly in Europe, tourists from the United States are likely to look at travel to other parts of the world, like the Far East.

Upon arrival in Tokyo the first shock comes as the tourist gets onto a bus. The 1972 bus fare of 40 yen has leaped to 110 yen, a boost of an astounding 175 percent. But not as astounding as the effective boost in the same fare for an American who spent 13 cents in 1972 and had to fork over 60 cents today -- for a leap of 362 percent.

What may be even more discouraging is the jump in the same fare just in the past two years. In 1976, the fare was 24 cents. That means it has increased 150 percent for Americans who are returning after a couple of years.

The slide of the American dollar has had a profound impact around the world. The dollar's purchasing power has dropped by 44 percent since 1972 in Germany and by about 40 percent in Japan.

The damage has been far more serious for Americans living overseas than for those just traveling.

In Germany, where car prices have been going up about 5 to 7 percent anyway for the past few years, a BMW 320I which cost $7,847 just last year now goes for $11,122. That's a 42 percent hike in one year.

A Volkswagen bus going for $3,623 in 1973 and $6,076 last year today sells for $8,635. That's up 68 percent from 1973 to 1977 and another 42 percent in the last year.

A men's shirt that was sold in a Paris department store for $14 in 1972 jumped to $19 in 1976 and is $22 now, but in most French shop windows these days, men's shirts have price tags of from $30 to $50.

The impact of the dollar's slide becomes even more clear with this example of how it has affected one American, a skilled professional who works in London for a large corporation with global interest. England is supposed to be one country where the dollar slide has not hit quite as hard on Americans because of the weakness of the pound sterling.

In 1972, he was getting paid $30,000 a year and the pound was worth $2.60. Four years later, his dollar pay had jumped by $7,200 and the pound had fallen to the point where it was worth only $1.78.

But all of those gains were wiped out by a wicked inflation. Consumer prices rose 82 percent during that period, and our worker's buying power of British goods and services actually fell by seven-tenths percent despite all of the other positive moves.

Today, his paper salary has risen to $42,000. But the falling dollar has lifted the price of the pound to $1.97 and British retail prices have jumped another 28 percent. So, the professional has suffered another 20 percent slash in his real income.

Actually, it gets worse. When the Labor government came back into power in 1974, it sharply increased the income tax levied on foreigners in Britain, costing the worker another several thousand dollars a year.

Why did he stay?

"I like working here," he said. "And was prepared to pay some price in real income for psychic income. Anyway, I kept thinking my company would understand the price-dollar-pound memos I sent off. They didn't. Now that Congress has increased U.S. taxes for Americans in Europe, I just can't hack it anymore. I'm going back to the States."