Ec 10 is not the monopoly it once was.

For the second consecutive year, the popular economics course Social Analysis 10, “Principles of Economics,” has seen enrollment significantly lower than that of previous years.

This year, 638 undergraduates have enrolled in the full-year course, only three more than last year. In contrast, enrollment from 1999 to 2003 ranged from 727 to 814, according to data from the Registrar’s website.

An increased number of introductory economics classes, a slow market and advanced placement into upper-level classes may account for this change in enrollment figures for Harvard’s perennial freshman favorite, which is taught by Baker Professor of Economics Martin S. Feldstein ’61.

Last year, Barker Professor of Economics Stephen A. Marglin ’59 launched a competing introductory economics course, Social Analysis 72, “Economics: A Critical Approach.”

Marglin has depicted his class as a one-semester liberal alternative to Ec 10.

Seventy-nine undergraduates enrolled in that course this year, compared to 78 last year. These numbers roughly coincide with the absolute decrease in Ec 10’s enrollment since 2003.

Feldstein said Marglin’s course could draw students interested in economics away from Ec 10.

“I think the primary reason [for Ec 10’s decline in enrollment] is the number of interesting econ course[s] offered without an Ec 10 prerequisite,” Feldstein wrote in an e-mail. “They don’t provide the same full coverage as Ec 10 but appeal to people who want some economics.”

Assistant Professor of Economics Silvia Ardagna, head section leader for Ec 10, offered other explanations for the decreased enrollment.

She speculated that more students use high scores on Advanced Placement exams to bypass Ec 10 in favor of upper-level classes.

Ardagna also said fluctuations in students’ interest in economics might be related to the state of the economy itself.

“My personal experience from enrollment at Wellesley College...tells me that the number of students who decided to major in Economics dropped as the economy slowed down and the stock market bubbles burst,” she wrote in an e-mail.

The number of economics concentrators in the College shrunk slightly last year, though it had increased each year from 1999 to 2002, according to the Faculty of Arts and Sciences Handbook for Students.

FILM BUFFS