VATICAN CITY — The number of Catholic bishops worldwide grew by almost 20% over a 20-year period, according to the Vatican's statistics office.

From 1978 to 1998, the number of bishops jumped from just more than 3,700 to more than 4,400.

The statistic is just one of thousands contained in the Annual Statistical Yearbook of the Church, which was to be published in mid-April, the Vatican announced April 3.

Even before its official release, the Vatican's statistics office offered a sneak peek at the information, reflecting data for the year ending Dec. 31, 1998.

The yearbook put the total number of Catholics throughout the world at about 1 billion. It said the Catholic population grew at a rate of 1.29 percent, which is just below the 1998 growth rate of 1.3% for total world population.

The Americas boasted the largest numerical increase in bishops since 1978, from more than 1,400 to more than 1,670, but Africa registered the biggest percentage jump — a 33% increase over the two-decade period.

Bishops’ geographic distribution remained largely the same, however, with the largest percentage of bishops, almost 38%, in the Americas.

Europe represented 33% of the bishops, followed by Asia with 14%, Africa with 12%, and Oceania with 3%.

The statistics office reported an overall downward trend in the number of priests since 1978, from more than 416,300 to more than 404,600, mostly due to a decrease in religious-order clergy.

But the number of diocesan priests increased worldwide from nearly 262,500 to more than 264,200, with Africa registering a 182% jump, from about 5,500 in 1978 to more than 15,500 in 1998.

Europe and North America reported decreases in diocesan and religious clergy. While the total number of priests declined, the numbers of permanent deacons, lay missionaries and catechists rose significantly over the past two decades.

“Such tendencies thus favor the manifestation of different choices in the pastoral worker corps,” said an April 3 press statement from the Vatican's statistics office.

In Africa, for example, catechists outnumber priests by more than 13-to-1; in the Americas, the ratio of lay missionaries to religious brothers is 3-to-1.