Ridership of Metrobus routes in the District of Columbia and suburban Maryland experienced little change, and may have declined after most recent fare increase in 1975 rather than increased at the transit authority public claims.

This possibly is suggested by the latest figures on revenue and estimated patronage released by Metro. Moreover, an actual count of Metrobus passengers in Virginia indicates a downtrend that ran counter to official Metro statements.

Although Metro personnel gathered the contradictory Virginia figures, they never have been openly presented to the Metro board, which was told by its staff of other calculations indicating the ridership trend is upward.

The board will soon decide on a suburban fare increase that is expected to take effect in mid-March.

Metro's own year-end press release reviewing the events of 1976 asserted without question that bus passengers increased "for the fourth straight year, up about five per cent to 128 million in spite of fare increases."

Higher patronage accompanying higher fares runs against the experience of the transit industry nationally and locally. Some Metro staff officials have defended the findings of more ridership, saying patrons were attracted by improved service and by fare reductions outside of rush hours. William I. Herman, Metro planning director, reiterated that view last week, and voiced doubt on the validity of the contradictory count.

Whatever the past trend, Herman predicted that the higher proposed fares in the future would lose about 1.5 million passengers a year, or about 5,000 a day, almost entirely on suburban routes.

Actual visual counts of passengers by trained personnel, conducted on two weekdays in October, 1975, and two weekdays in November, 1976, showed a patronage decline of 5.4 per cent. Metro planning officials insisted these figures are reliable, and that the method used to collect them in both years was identical and assured the comparability.

The all-day count showed that in 1975, a total of 1,232 bus trips carried 56,955 passengers, an average of 46.2 persons per trip, including rush-hour standees. This set a record for bus ridership across the Potomac.

In 1976, the number of such trips increased to 1,243, but the passenger count declined to 53,905 or 43.4 persons per trip.

In 1975, Metro introduced a novel dual fare in suburban routes, with higher charges during rush hours than at other times. Only in the District of Columbia did fares remain at the same level at all hours, with the city government choosing to increase its subsidy of the bus deficit.

An increase of the rush-hour fare in the city from 40 to 50 cents has been recommended by a Metro board committee.

With the new fares in the suburbs, revenues went up sharply. So did the official estimate of the number passengers carried, although the increase on Virginia routes was less than elsewhere.

Delmer Ison, Metro's secretary-treasurer, whose office handles fare collections and is responsible for compiling patronage statistics, acknowledged in an interview that his figure for the number of passengers is unreliable.

Although the revenue figure is precise (it is an actual count of money dropped into bus fare boxes) the ridership figure is only an estimate, Ison said.

Metro cash fares vary from 20 cents to $1.20 on regular city and suburban routes. No routine count is made on the number of individuals who drop those fares into the boxes.

Staff employees have calculated what they believe to be the average fares for buses at each of Metro's eight garages, and simply divide these averages into the amount of money collected to derive the ridership estimates.

The latest revenue figures and ridership estimates presented Jan. 27 by Ison to the Metro board tends, on analysis, to support the thesis that ridership declined after the 1975 fare increase but is now holding steady.

Ison's report shows that fare collections and estimated riders for each of the earlier months of 1976 exceeded the figures for the same months of 1975, when the fares were lower.

But starting in September, when identical fares were being compared, the trend abruptly leveled off, indicating that patronage had become stagnant. Fare collections during September, October and November, 1976, were almost precisely $15 million, an increase of only one-tenth of one percent over the previous year.

By Metro's reckoning, patronage rose to 32 million from the previous 31.7 million for the three-month period. Broken down by operational divisions, the revenue figures showed that collections on the Alexandria Division were down about five per cent. This includes many of the long Shirley Highway Express routes where the actual count of passengers showed a decline.

The Arlington and Prince George's Divisions were up by small amounts, while the four garages that dispatch bus routes in the District of Columbia, Montgomery County and northwestern Prince George's showed virtually no change.

Because of zone boundary changes, Maryland routes did not experience as large an average fare increase in 1975 as the Virginia routes, and surcharges for express service were eliminated.

On the Metro Board, Joseph S. Wholey, the first vice chairman, who also is chairman of the Arlington County Board, has vocally defended a policy of escalating fares, citing the apparent continued rise in patronage despite rising fares.

During a Metro board meeting last Thursday, Wholey said: "I consider that we get sufficiently accurate information for policy purposes . . . for (deciding) fare increases . . ."

"Well, I don't," shot back Douglas N. Schneider Jr., director of the D.C. transportation department and a board member.

Herman, the Metro planning director, said he doubts the worth of the actual passenger counts, since they were conducted in different months of the two years, and November ridership is usually lower than that of October. Moreover, he said, he understood htere were differences in weather conditions that might account for the discrepancy.