Here is an interesting article about 1 year eGFR decline rates among people with type 2 diabetes with eGFR>60:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5743850/ 

Some highlights:

- We calculated 1-year eGFR decline rates from the difference between each eGFR value and that of the previous year. We examined the prediction capacity of 1-year eGFR decline rate for renal prognosis. When we performed receiver operating characteristic analysis, the area under the curve of 1-year eGFR decline rate was 0.963 (95% confidence interval: 0.953–0.973). With a cut-off value of more than 7.5% eGFR decline during a 1-year period, the sensitivity was 98.8% and specificity was 82.3%. The predictive accuracy of 1-year eGFR decline rate for renal prognosis was high.

- In 2009, more than 871,000 people were treated for ESRD, and between 1980 and 2009, the prevalence of ESRD increased nearly 600%, from 290 to 1,738 cases per million in the United States. ESRD treatment costs the United States over $40 billion in public and private funds in 2009. The life expectancy of patients with ESRD has remained poor, and ESRD prevention is challenging (data from the web site of National Institute of Diabetes and Digestive and Kidney Diseases; https://www.niddk.nih.gov/health-information/health-statistics/Pages/kidney-disease-statistics-united-states.aspx. last accessed, September 28, 2016). The cardiovascular disease prognosis in patients with type 2 diabetes has markedly improved over the past 20 years, but the incidence of ESRD has decreased very little.3) Until the microalbuminuria stage, tight glycemic control can slow the progression of nephropathy. The Steno-2-study showed intensive treatment in patients with microalbuminuria could reduce cardiovascular disease events, all-cause mortality, and the need for dialysis.4,5) Thus, early interventional treatment for diabetic nephropathy is important.

- GFR generally declines at a rate of 1 mL/min/year. However, patients who lose renal function faster than the average age-related decline in GFR tend to progress to ESRD.

- We divided the study subjects into two groups based on whether their maximum 1-year eGFR decline rate was <7.5% or ⩾7.5%; the clinical background of each group is shown in Table ​

Table4.- The average observation period was shorter in the group with a decline rate ⩾7.5%. Baseline high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and hemoglobin were lower in the group with a decline rate ⩾7.5%, and HbA1c, glucose, C-reactive protein, triglyceride, gamma-glutamyl transpeptidase, and albuminuria at baseline were higher in the group with a decline rate ⩾7.5% (Table ​(Table4).4). Diabetic retinopathy was significantly more frequent in the group with a decline rate ⩾7.5%. Body mass index and the prevalence of hypertension, which was defined as a systolic blood pressure ⩾140 or diastolic blood pressure ⩾90 mm Hg or the use of antihypertensive drugs, were not different between groups. Angiotensin receptor blockers were significantly more frequently prescribed in the group with a decline rate ⩾7.5%. Furthermore, the group with a decline rate ⩾7.5% used more oral hypoglycemic agents and insulin than did the group with a decline rate <7.5%. 

- In this study, we selected patients with baseline average eGFRs of ≥60 mL/min/1.73 m2, because subjects who already had decreased renal function were inevitably susceptible to reach the endpoint. It is not clear if our eGFRmonthly smoothing data trajectory method can also predict renal prognosis in subjects with eGFRs < 60 mL/min/1.73 m2.