4. Changes to the person's business operations or organizational structure.
Example: The person began selling a new line of products in the audit period.
(4) Criteria For Statistical Sampling. All of the following criteria must be met before statistical sampling may be used on a sample population.
(a) All accounting transactions must be maintained in an electronic format and must be capable of secure electronic transfer to the department, in a form useable by the department.
(b) The data processing accounting system must be capable of producing and transferring to the department an electronic spreadsheet of all accounts for each period under audit, including account number, account description, and year-end and pre-closing balances.
(c) All electronic sales transactions must include the following:
1. Customer name
2. Electronic transaction number that identifies and leads to the source document
3. Electronic transaction date
4. Electronic transaction amount
5. Information necessary to determine where sourced under s. 77.522, Stats. (d) All electronic purchase transactions must include the following:
1. Vendor name
2. Electronic transaction number that identifies and leads to the source document
3. Electronic transaction date
4. Electronic transaction amount
5. Account number from accounting system or other information that identifies where the purchased item was stored, used or consumed
(e) Documentation used to prepare each sales and use tax return filed with the department to report sales and use tax paid must be available for review by the department, including transaction detail, reports, and work papers.
(f) All sample unit source documents must be available for review by the department.
(g) There are at least 10,000 sample units in the sample population.
(5) Maximum Sample Size. (a) Except as provided in par. (b), the maximum number of sample units selected for review for each sample population from which a statistical sample is drawn may not exceed 10 percent of the sample population or 15,000 transactions, whichever is less.
(b) Paragraph (a) does not apply if the relative precision of the sample is greater than 20 percent. In determining an acceptable sample size, the department must consult with the person.
Example: If the relative precision of a sample is 20 percent and the net error is $100,000, there is 90% confidence that the true error of the sample population is between $80,000 and $120,000.
SECTION 2. Effective date; general. This rule shall take effect on the first day of the month following publication in the Wisconsin Administrative Register as provided in s. 227.22 (2) (intro.), Stats.
