Warranty Data Entry Types

Weibull++ allows for data entry utilizing three common formats for storing sales and returns information. Specifically:

Nevada Chart Format

Field information frequently appears in terms of units produced and/or shipped in a certain time period, with the resulting returns for that production lot in the subsequent time periods. This information can be arranged in a diagonal chart, as displayed in the following figure. (Note: Sometimes named after a state, based on the way the data are arranged, i.e. "Nevada chart", "Idaho chart", etc.)

Time-to-Failure Format

This format is similar to the Standard Folio data entry format (all number of units, failure times and suspension times are entered by the user), as discussed previously. The difference is that when the data is used within the context of warranty analysis, the automatic ability to generate forecasts is available to the user. In Weibull++ this window is as shown next:

Dates of Failure Format

Another common way for reporting field information is to enter a date and quantity of sales or shipments, Quantity In-Service Data , and the date and quantity of returns, Quantity Returned Data, as illustrated in the following tables.

Quantity In-Service	Date of In-Service
400	1/1/2005
500	1/31/2005
500	5/1/2005
600	5/31/2005
550	6/30/2005
600	7/30/2005
800	9/28/2005
200	1/1/2005
350	3/2/2005
450	4/1/2005
300	6/30/2005
200	8/29/2005
350	10/28/2005
1100	2/1/2005
1200	3/27/2005
1200	4/25/2005
1300	6/1/2005
1400	8/26/2005

Quantity Returned	Date of Return	Date in-Service
12	1/31/2005	1/1/2005
7	7/22/2005	5/1/2005
8	8/27/2005	5/31/2005
12	12/27/2005	5/31/2005
13	1/26/2006	6/30/2005
14	1/11/2006	9/28/2005
15	1/18/2006	9/28/2005
23	1/26/2005	1/1/2005
16	1/26/2005	1/1/2005
18	3/17/2005	1/1/2005
19	5/31/2005	3/2/2005
20	5/31/2005	3/2/2005
18	7/30/2005	4/1/2005
19	12/27/2005	6/30/2005
18	1/11/2006	8/29/2005
34	8/14/2005	3/27/2005
24	8/27/2005	4/25/2005
44	1/26/2006	6/1/2005
26	1/26/2006	8/26/2005

Note that in order to identify which lot the unit comes from, a failure is identified by a return date and the date of when it was put in service. The date that the unit went into service is then associated with the lot going into service during that time period. Lots can be used with the optional ID column which is covered in the sections that follow.