A couple of years ago I wrote an article about “the Passover test” - what the Seder reveals about interfaith couples. Here’s what I wrote:
Five traditional Jewish practices are usually used as criteria in studies tasked with assessing the viability of a Jewish community: lighting Hanukkah candles, attending a Passover Seder, fasting on Yom Kippur (the Day of Atonement), lighting Shabbat candles, and keeping a kosher home. The first two—Hanukkah-candle lighting and Seder attendance—tend to be those with the highest levels of participation among the vast majority of Jews.
This was not something I invented - it is what I learned from studies of the American Jewish community. According to the National Jewish Population Survey, 67% attend a Seder, 72% light Hanukkah candles, and 59% fast on Yom Kippur. And as I noted in the post:
The correlation between the Hanukkah-candle lighting and the Passover Seder—the two most practiced rituals among American Jews—is interesting. Hanukkah is more popular for most Jewish groups. The reason is clear: The holiday competes with Christmas. However, the more affiliated the group, the narrower the gap between these two practices. The “highly affiliated” is the only group in which Seder attendance surpasses Hanukkah candle lighting (96 percent to 94 percent, according to the National Jewish Population Survey). For the intermarried—couples with one Christian spouse—the gap between the two practices is the widest (85 percent celebrate Hanukkah; 41 percent celebrate Passover).