350 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28

If it is now assumed that the amortisation periods for equipment
 and structures are respectively 5 and 20 years (1), and if
it is further assumed that the average production period for
equipment goods is (Hypothesis H”)

® = 4.23

‘his leads to assessing at 10 and 25 years respectively the approximate
 length of the amortisation period of the primary
inputs incorporated in equipment and structural assets.
If it is assumed that all investment consists of durable
goods, and maintenance and repair outlays are abstracted,
the position can be summarised as in Table 10 below (in $ billion)
 on the basis of the estimates in § 333-6 (2).

TABLE 10

(nventories
Zquipment
Structures

- +
. .

Total

Equipment and
Structures .

[22.3
340.8
726.6

[190.7

1077.4 |

RA

199.5
34.1
20.5

262.1

63.6 !

C/Ra

0.61
Io
26

4.56

16.04 |

C | Re:
n % in %

10.2
28.4
61.4

75-9
13.0
II.1

TON

ra

80.8 |

24.1

() These are the figures used by various fiscal administrative agencies.
(?) The values of R, for equipment and structural assets are obtained
y dividing the figures in the first column into those in the third. The
?, figures for inventories are then obtained bv difference

263. T — 34.1 — 20.5 = 100.4

11] Allais - pag. 154