"decline ratio" is correct and can be used in written English.
It is often used in business or economics writing to refer to the ratio of decrease in a certain measure such as profit or production. For example, "The decline ratio of the company's stock has steadily increased over the past five years."
Then, the fouling decline ratio was determined using trypsin as a model protein.
The results indicate that the effective thermal conductivity of composite materials decreases as the thermal conduct resistance increases and the decline ratio will gradually slow down.
The biofilm thickness on the membrane surface after the biofouling tests was positively related to the decline ratio of the permeate flux.
Flux decline ratio (JFD) value was calculated to reflect the fouling resistance ability of the membrane by the following equation: J_{text{FD}} = left( {1 - frac{{J_{text{P}} }}{{bar{J}_{text{W}} }}} right),, times,1000.
Flux decline ratio (RFD) value is introduced to reflect the fouling resistance ability of the membrane; a lower value of RFD means a higher fouling resistance ability of the membrane.
Meanwhile, the hybrid membranes exhibited a preferable antifouling property, that is, high flux recovery ratio (ca. 92%) and low total flux decline ratio (ca. 0.26) when CS MMT content was only 1.0 wt.%.
But this declining ratio is deceptive.
Add in the increase in the public sector workforce in recent decades and the declining ratio of workers to pensioners, and you arrive at the second reason ministers think something has to be done: cost.
Right now, given reasonable estimates of likely future growth and inflation, we would have a stable or declining ratio of debt to G.D.P. even if we had a $400 billion deficit.
If I'd opted to go by air, I might have shaved two or more hours off that total, driving 11 miles to our local airport and switching planes in Los Angeles, but that option never crossed my mind (flight delays, the cattle car, the indignities of the search and the Torquemadaean contortions of the ever-declining ratio of leg bone to seat-space).
Crawford also cites a declining ratio of new highs to new lows, as well as a rising Volatility Index (VIX).
