I hope you know you’re not the only person deluged by automated telephone marketing campaigns known as “robocalls” that often skirt legality.

Let me show you what I learned from YouMail, an Irvine-based provider of voicemail and phone-security services, and its estimates of local robocall activity. The details are derived from its database of telephone calls it manages for its 8 million clients.

For example, my trusty spreadsheet tells me that 15 Southern California area codes were hit with 162.4 million robocalls in July. Not only is that up 2 percent in a year, it’s equal to one every six days or 5.2 calls per line for the month.

“It’s just like email; when it got cheap we got spam,” says YouMail CEO Alex Quilici. “As phone calls became extremely cheap we see an explosion of robocalls and robocall scams.”

Reviewing YouMail data by area code reveals that robocall frequency varies widely by geography. For example, folks in West Los Angeles in the 310 area code in July were almost six times as likely to get a robocall as those in Downtown L.A.’s 213. And in South Orange County’s 949, robocalls occur at almost triple the per-capita pace as they do in central L.A.’s 323.

Quilici says robocallers, especially the scammers, are no dummies and tend to target communities where they think their calls can win the most business. And since many scammers offer phony services to the financially challenged, areas with monetary pressures are often hard hit. As are residential regions vs. business districts.

Here’s a look a robocall frequency in Southern California area codes in July vs. a year ago. (Note: No YouMail estimates were available for area codes 442, 657 and 747.) The list is ranked by most likely to least likely …

1. 310 (western L.A.): One robocall every 3.3 days vs. every 3.5 days in 2016.

2. 949 (south Orange County): every 3.8 days vs. 3.7 days.

3. 818 (San Fernando Valley): every 4.2 days vs. 4.3 days.

4. 714 (north Orange County): every 4.3 days vs. 4.6 days.

5. 619 (San Diego): every 4.7 days vs. 4.5 days.

6. 760 (Deserts): every 5.6 days vs. 5.8 days.

7. 626 (L.A. east): every 6.2 days vs. 6.7 days.

8. 805 (Ventura): every 6.3 days vs. 6 days.

9. 951 (Riverside): every 6.6 days vs. 7 days.

10. 909 (San Bernardino): every 6.7 days vs. days.

11. 562 (Long Beach): every 6.9 days, same as ’16.

12. 858 (North San Diego): every 7.8 days vs. 8.6 days.

13. 424 (Western L.A.): every 10.0 days vs. 10.7 days.

14. 323 (Central L.A.): every 10.3 days vs. 10.7 days.

15. 213 (Downtown L.A.): every 18.2 days vs. 15.5 days.

So how can one limit robocalls?

“It’s like your mother said. Don’t talk to strangers. Protect yourself. And do your homework,” YouMail’s Quilici said.

You can place your phone numbers in the National Do Not Call Registry (https://www.donotcall.gov). Or try various options built into your phone or provided by your service provider. And there are third-party apps, cloud-based services and call-blocking tools you can try.

And there’s hope unwanted calls will be curtailed, says Quilici who sees another parallel to email in the cleanup. Once spam became truly annoying, various players in the industry united to fight the scourge.

“Spam is a non-issue for many people today,” he says. “I see the exact same trend with phone calls. Just robocalls are more annoying than spam.”