Fans frustrated by the Cubs’ bullpen coughing up leads in the late innings should know two things:

1. You are not alone.

2. As with their other troubles this season, the Cubs’ bullpen problem has been worse on the road.

Through Sunday, major-league teams had converted 63 percent of their save opportunities. That’s the lowest conversion rate since 61 percent in 1974.

The 1974 dip was an outlier. Relievers had been successful in 72 percent of save opportunities in 1973 and bounced back to 68 percent in 1975.

About 68 percent is normal. Major-league averages often topped 70 percent in the 1960s through 1980s, and there have been occasional 70 percent-plus seasons more recently.

In the 10 years starting in 2009, relievers converted 67, 69, 68, 70, 68, 69, 69, 68, 66 and 66 percent of save chances.

In 2019, six teams have converted 70 percent or more of their save opportunities, led by the Cardinals at 79 percent. The Cubs are lagging behind at 57 percent. The difference between their 31 saves in 54 chances and the Cardinals’ 38 in 48 looms large in a tight National League Central race.

In four consecutive playoff seasons, the Cubs have exceeded major-league averages. They converted 72 percent in 2015 and 2016, 67 percent in 2017 and 71 percent in 2018.

Craig Kimbrel, just back from the injured list, has been by far the most successful Cubs reliever at closing out victories, with nine saves in 11 chances.

Manager Joe Maddon has given save opportunities to 13 pitchers this season. The latest, Rowan Wick, saved the Cubs’ 2-0 victory Saturday against the Pirates. That was Wick’s first appearance with a save on the line. He’s the only Cubs reliever who has a save opportunity without a blown save.

The Cubs have 21 saves in 33 chances at home, a 63.6 percent success rate that’s a hair above the major-league average. But they’re 10-for-21 for 47.6 percent on the road.

Pedro Strop, who leads the Cubs with 10 saves but only has one since June 23, breaks down to 8-for-12 at home and 2-for-4 on the road. Kimbrel is a perfect 6-for-6 at home but 3-for-5 on the road.

The anomaly has been Steve Cishek, who is 7-for-10 overall but a perfect 4-for-4 on the road. Cishek, however, has been hit hard since the All-Star break. Before the break, he had a 2.75 ERA and opponents had a .562 OPS against him. Since the break, the numbers are 6.55 and 1.006.

Save opportunities in road games are a small sample. The numbers don’t say Tyler Chatwood, with two saves at home, is a subpar choice on the road. They just say he has been unsuccessful in one opportunity.

A group effort from the bullpen has contributed to the Cubs’ 25-39 road record. The Cubs have scored 308 runs and allowed 313 on the road. That translates to a 31-33 Pythagorean projection, but they need to protect late leads.