What survey is this? I'm not sure I understand your statement "sample size is calculated for an error, in the mean of the income variable, less than 3% with a confidence level of 3 per thousand" You could assume it is a simple random sample if you really don't know anything else. Note the survey design only impacts variances, standard errors, and test statistics, it doesn't impact point estimates like means and totals. Here's an example using the srvyr/survey package:

```
library(survey)
#> Loading required package: grid
#> Loading required package: Matrix
#> Loading required package: survival
#>
#> Attaching package: 'survey'
#> The following object is masked from 'package:graphics':
#>
#> dotchart
library(tidyverse)
library(srvyr)
#>
#> Attaching package: 'srvyr'
#> The following object is masked from 'package:stats':
#>
#> filter
# In this example, the data apiclus1 has a weight of pw
# We will pretend it is from a simple random sample
# https://cran.r-project.org/web/packages/srvyr/vignettes/srvyr-vs-survey.html
data(api) # this loads in some example data from survey package
my_des <- apisrs %>%
as_survey_design(ids=1, #no cluster
weights=pw
)
# Making a frequency table using a survey object
my_des %>%
group_by(awards) %>%
summarize(proportion=survey_mean(),
total=survey_total())
#> # A tibble: 2 x 5
#> awards proportion proportion_se total total_se
#> <fct> <dbl> <dbl> <dbl> <dbl>
#> 1 No 0.38 0.0344 2354. 213.
#> 2 Yes 0.62 0.0344 3840. 213.
svyplot(api00~api99, design=my_des)
```

^{Created on 2020-04-28 by the reprex package (v0.3.0)}