$TPAC I'm going to assist a couple of brilliant and inquiring minds with a comparative in definitions.
Decrease: de·crease
verb
d?'kres/
1.
make or become smaller or fewer in size, amount, intensity, or degree.
"the population of the area has decreased radically"
synonyms: lessen, reduce, drop, diminish, decline, dwindle, fall off; More
noun
'de?kres,d?'kres/
1.
an instance or example of becoming smaller or fewer.
"a decrease in births"
synonyms: reduction, drop, decline, downtrend, downturn, cut, falloff, cutback, diminution, ebb, wane
"a decrease in crime"
Increase: in·crease
verb
in'kres/
1.
become or make greater in size, amount, intensity, or degree.
"car use is increasing at an alarming rate"
synonyms: grow, get bigger, get larger, enlarge, expand, swell; More
noun
'inkres/
1.
an instance of growing or making greater.
"an increase from sixteen to eighteen clubs"
synonyms: growth, rise, enlargement, expansion, extension, multiplication, elevation, inflation; More
Application Question:
If the share structure is being reduced and shares are being retired on an ongoing basis with no dilution, which definition is most likely to apply?