The Slide Rule Trading Co., Paul Ross

Hemmi Slide Rule Catalogue Raisonne

Hemmi P402/P403
This material, including illustrations, provided by Atsushi Tomozawa.

Hemmi P402 and P403 are special rules designed by Tanabe Consulting Co., Ltd. for "Corporate Performance Analysis", and manufactured by Hemmi. P402 is intended for companies in manufacturing industry and P403 is for distributive trades such as whole sale and retail stores. 

The instruction book devotes about half of pages to discussion of Tanabe's methodology of evaluating the corporate performance. The second half is the details of how to use the slide rule.

Uniqueness of these rules is tied to the method for analysis. Therefore, I will focus on the methodology of the analysis first and then describe briefly how the slide rules are used.

The two types of designs differ only slightly. In the following, P402 will be used to illustrate the use of the rules. 

Corporate Performance Analysis

Tanabe Consultant uses 10 corporate performance indices, grouped in four categories for corporate performance analysis as listed below. Each performance index is allocated a maximum point. The total of the points is 100.

Actual points are computed from the actual corporate performance data, and by totaling the points, the company's performance value is obtained. How to interpret the final number is not explained in the document. Perhaps you might need the services of the Tanabe Consultant.
 
Index Category Performance Index Max. Allocated Point Class Point
1
 Profitability Operational Profit per Total Asset(%)
15
See below
2
 Operational Efficiency at Marginal Profit (%)
10
3
 Product Strength Marginal Profit Ratio (%)
15
4
 Sales Growth (% per year)
10
5
 Money Total Equity to Gross Capital Ratio (%)
10
6
 Total Equity Growth (%)
5
7
 Interest Paid per Sale (%)
10
8
 Liquidity Index (%)
5
9
 Human Resources Operational Profit per Person
10
10
 Added Value per Person
10
Total 100

Figure 28 
Point is determined by the value of the performance index. First the value gets classified into one of the four classes; A, B, C and D. Each class has the appointed point. The table below shows the classification and point assignment for the first and second indices (Operational Profit per Total Asset and Operational Efficiency at Marginal Profit.) The table shows that, for index 1, the point is 15 for the index value of 20% or more, 12 points for the values between 12 and 20% and so on. See the original Table 28 for the complete point assignment.
Index  Classification Criteria Point
Class A Class B Class C Class D A B C D
1
20 and above
12-20
6-12
below 6
15
12
9
6
2
below 70
below 80
below 90
90 and above
10
8
6
4
Figure 28 Right (Partially Transcribed)

Using P402/403 Slide Rule


Left-half of Hemmi P402
(Circled numbers and English text in red do not appear on actual rule.)


Right-half of Hemmi P402

There are three 4 cycle logarithmic scales on the front side of the rule. One on the upper body, the second on the upper side of the slide and the third on lower stator body. The first two are aligned with each other while the third scale is offset by a small amount. There are four "Gauge Points" or indices on the slide; corresponding to four groups of performance indices.

There are additional 10 paired scales referenced by numbers 1 through 10 as seen in the above pictures. Each one corresponds to one of the performance indices discussed above. The pair consists of the percentage index and resulting point. Some of the percentage scales are independently drawn and some are read off on the main scales.

Now you've gotten the general layout of the rule, you are ready to use it. Only one example is given since the operations are very similar for the other computations.

Problem: Compute the Operational Profit per Total Asset and corresponding point for it. Assume that the operational profit = 9 Million Yen and the total asset = 83 Million Yen.

Solution: Align 90 on the upper body scale with 830 on the slide, move cursor to Profitability index on the slide, read the % on (1) scale (8%) and points (9) on the associated scale.