What is the use of イ. in this document?


While reading this
[page](https://www.boj.or.jp/announcements/release_2020/rel200909a.pdf), which
is about the Bank of Japan, I came across イ.

日本銀行は、日本銀行当座預金のうち、ゼロ金利が適用されるマクロ加算残高 の算出に用いる基準比率(「補完当座預金制度基本要領」4.(3) **イ.**
に定める 基準比率)について、次のとおり定めることとしました。

I am not sure about the meaning of it. Is it interest?




「イ」is part of the numbering format for legal documents and is used to for
subsections.

The order is
[いろは順](https://ja.wikipedia.org/wiki/%E3%81%84%E3%82%8D%E3%81%AF%E9%A0%86),
and would go: イ、ロ、ハ、ニ、ホ、ヘ、ト... In English this would be "a, b, c..." or maybe
"i, ii, iii..."

If you read the announcements correctly, is says:

> ...the benchmark ratio (as determined under 2.3.イ in "Principal Terms and
> Conditions of Complementary Deposit Facility" has been determined as
> follows.

So you would need to look up the specified article (2.3.イ) in the specified
document
["補完当座預金制度基本要領"](https://www.boj.or.jp/mopo/measures/term_cond/yoryo37.htm/).
(There is an [English
version](https://www.boj.or.jp/en/mopo/measures/term_cond/yoryo36.htm/) of the
document, and there it is listed as 2.3.a.

If you want to read up on the basic formatting of legal documents, Wikipedia
has an
[article](https://ja.wikipedia.org/wiki/%E6%97%A5%E6%9C%AC%E3%81%AE%E6%B3%95%E4%BB%A4%E3%81%AE%E5%9F%BA%E6%9C%AC%E5%BD%A2%E5%BC%8F).
This [pdf](http://www.hpsca.hokkaido-c.ed.jp/63kenkyuutaikai/oshima/23.pdf)
also makes it easy to visualize.

