LObiadi

The processing times reported by USCIS for the I-130 should not be interpreted as the average time it takes to process a case. The reported times used a "cycle time methodology" which you can read about here: Case Processing Times (uscis.gov).
 
Basically, you pick reference month and see how many cases are pending. Then you calculate how many previous months of cases it takes to match the reference month's pending cases. USCIS doesn't release how many cases they receive each month for the I-130, but they do release quarterly cases (located here Immigration and Citizenship Data | USCIS). Let's work through a real example in the Texas Service Center.
 
In Jul-Sep 2021, Texas had 69,088 pending I-130 IR1/CR1 cases.
 
In Apr-Jun 2021, they received 21,888
In Jan-Mar 2021, they received 18,737
In Oct-Dec 2020, they received 19,653
 
21,888 + 18,737 + 19,653 = 60,278.
 
So it takes roughly 9-months (Oct 2020-Jun 2021) of receipts to equal the number of pending cases for Jul-Sep 2021. In Aug 2021, the wait time for Texas was 9.0 - 11.5 months, which is exactly what you would expect given the data USCIS provides. I understand this to mean that if you applied in Oct-Dec 2020, you should expect your case to have been processed by Jul-Sep 2021. I view this as an imperfect methodology but it likely gets you in the ballpark. I think the major issue with this method is it doesn't account for complex cases that take longer to process. Those cases will sit, but USCIS expects even those cases will be processed by the upper limit of the range. Only if a case is outside of that range can a person inquire about their case. 
 
You can imagine that if a service center receives a growing number of cases but their ability to process those cases stays the same, it will quickly grow the timeline for processing. Conversely, if they receive fewer cases or expand their ability to process cases, the time will lower.
 
The better methodology many USCIS forms use is the "Processing Time Methodology." They first calculate the amount of time it took to make a judgement on every case (e.g., approve, deny) in the last 6-months for a given form. Then they take the median of that number (50th percentile). That is the lower range. They also calculate the 93rd percentile and that is the upper range. If the lower-upper range was 9-15 months, that means that 50% of cases were processed within 9 months or less and 93% of cases were processed within 15 months or less. Interestingly, they do use this methodology for the historical processing times, but that data is provided overall for all service centers and for immediate relatives only. That information can be found here: Historic Processing Times (uscis.gov)
 
The thing I don't understand and I haven't seen addressed elsewhere is why some cases seemingly get processed much faster. Using the Texas Service Center above, you would expect non-complex cases submitted in Oct-Dec 2020 would get processed before Jan-Jun 2021 cases, but we have all seen examples of when that doesn't happen. Although, in general, they do seem to process them in a first in, first out process. 
 

I waited for the notification. One of the required documents to be submitted for a spouse K3 visa I-129f is the I-130 notification received by mail.

Timelines are so important for us to know when u married and when u applied
no timeline so i am reading a past post of yours which looks like married 2021 and filed last spring 
 
USC should file as married (either joint or separate but joint shows u start to commingle assets and makes your case stronger)
IRS is slow (per their announcement to do tax returns this year for all of us) so following the iRS site to apply for his ITIN will not slow them down as we are looking at slow returns 
 
follow IRS guides 
 
https://www.irs.gov/individuals/international-taxpayers/nonresident-spouse
 
important is the amount of time u spend together 
and u r still looking at about a year to get to the interview (if spring 2021 petition)
Nigerian should do a POA to give spouse the right to do business in the US in in his name (to add name to bank account after the ITIN is assigned) 
u can both do a will assigning the other as a beneficary (along with her children)

Thank you.

I am a U.S. citizen, who married a Nigerian in South Africa on July 5, 2021. I went to visit him for 2 weeks this month, and unexpectedly got married. So here I am, trying to learn the correct and efficient way to get him over here to the U.S..
So of course I came back to the U.S. by myself, which was ok, because we both have things to organize before he comes over, so we were anticipating April 2022, even if, hypothetically, his I-130 would be approved before that. Since the whole marriage thing happened unexpectedly, I had to do some quick research on how we get him to the U.S. When I briefly read that we could apply for a Spouse Visa, while the I-130 is pending, we just assumed that it would be realistic to think he could be here with me for good, next April. But then some people told me to not apply for the spouse Visa, as it's a waste of time and money. Then I read somewhere, that only 5 Spouse Visas were approved in 2020??!! Some people tell me that the I-130 can take over a year to get approved, but some people tell me that since I'm a U.S. citizen, that it shouldn't take more than about 9 months. Im just very confused on what to do and how to prepare myself for all of this. We filed the I-130 this week. Do I just wait and see what happens, since we weren't planning for him to come til next April? Im going back in January 2022, for 2 weeks. I'll be so frustrated if it takes a year or more, before he can be here. It's hard enough to have to now wait 5 months to see my new Husband, but to have to wait a year or more, for us to be physically together for good, seems like it would be so hard. Advice, suggestions?? Thanks in advance.

He can try .. best to apply for a B1/2 visitor visa prior to submitting the I 130 paperwork .. once the I130 is submitted he will be known to have immigrant intentions .. which will make being granted a visitor visa much less likely ..